1000000
34.00
47000
28595796
501000
499000
228847000
25077000
1383000
25077000
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9.59
4112000
806000
9.64
338000
5000000
4058000
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125000000
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0.01
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276315000
6550000
2586000
39547000
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165756000
6550000
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25291000
8056000
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240622000
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74866000
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30100000
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240622000
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43759000
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20100000
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175710000
175710000
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67011000
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250103000
4359000
34874000
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239000
224390000
693000
72723000
30208000
211987000
206279000
224390000
206279000
5015000
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206279000
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P3Y
P9Y
P5Y
209000
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-11127000
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bluebird bio, Inc.
false
Non-accelerated Filer
2014
10-Q
2014-06-30
0001293971
--12-31
Q2
<div>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt">
<b>7. Stock-based compensation and warrants</b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
In 2013, the Company’s board of directors and stockholders
approved the 2013 Stock Option and Incentive Plan (“2013
Plan”) which allows for the granting of incentive stock
options, non-qualified stock options, restricted stock and
restricted stock unit awards, as well as other equity awards to the
employees, members of the board of directors and consultants of the
Company. The 2013 Plan replaced the 2010 Stock Option and Grant
Plan. In January 2014, the number of shares of common stock
available for issuance under the 2013 Plan was increased by 960
shares as a result of the automatic increase provision of the 2013
Plan. As of June 30, 2014, the total number of shares of
common stock available for issuance under the 2013 Plan was
806.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt">
<b><i>Stock-based compensation expense</i></b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
Stock-based compensation expense by award type was as follows:</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 12pt; MARGIN-TOP: 0pt">
 </p>
<table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="92%" align="center" border="0">
<tr>
<td width="72%"></td>
<td valign="bottom" width="3%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="3%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="3%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="3%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman">
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="6" align="center"><b>Three months<br />
ended June 30,</b></td>
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="6" align="center"><b>Six months ended<br />
June 30,</b></td>
<td valign="bottom"> </td>
</tr>
<tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman">
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>2014</b></td>
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>2013</b></td>
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>2014</b></td>
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>2013</b></td>
<td valign="bottom"> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Stock options</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">2,335</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">1,623</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">4,812</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">2,262</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Restricted stock awards</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">16</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">34</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">31</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">56</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top"></td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">2,351</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">1,657</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">4,843</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">2,318</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%">
As of June 30, 2014, there was $21,288 of unrecognized
stock-based compensation expense related to unvested stock options
and restricted stock awards that is expected to be recognized over
a weighted-average period of 3.0 years.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%">
During the six months ended June 30, 2014, the Company issued
2 shares of restricted common stock in exchange for consulting
services. The shares vested upon issuance and the Company
recognized $42 of expense related to the services provided.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%">
During the six months ended June 30, 2014, 123 options held by
former employees were modified to extend the expiration date. The
modification was valued using a Black-Scholes option valuation
model and the Company accounted for the $643 of incremental value
within general and administrative expenses.</p>
<p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 1px; MARGIN-TOP: 18px">
 </p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 0pt">
<b><i>Restricted common stock</i></b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 12pt; MARGIN-TOP: 0pt">
 </p>
<table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="76%" align="center" border="0">
<tr>
<td width="74%"></td>
<td valign="bottom" width="10%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="10%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman">
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>Shares</b></td>
<td valign="bottom"> </td>
<td valign="bottom"> </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b><font style="WHITE-SPACE: nowrap">Weighted-average</font><br />
grant date<br />
fair value</b></td>
<td valign="bottom"> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Unvested balance at December 31, 2013</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">69</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"> </td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">0.95</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Granted</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom" nowrap="nowrap"> </td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"> </td>
<td valign="bottom" nowrap="nowrap"> </td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Vested</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">(42</td>
<td valign="bottom" nowrap="nowrap">) </td>
<td valign="bottom"> </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">0.95</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Forfeited</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom" nowrap="nowrap"> </td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"> </td>
<td valign="bottom" nowrap="nowrap"> </td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Unvested balance at June 30, 2014</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">27</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt"> </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">0.95</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt">
<b><i>Stock options</i></b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
The following table summarizes the stock option activity under the
Company’s equity award plans:</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 12pt; MARGIN-TOP: 0pt">
 </p>
<table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="76%" align="center" border="0">
<tr>
<td width="81%"></td>
<td valign="bottom" width="5%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="5%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman">
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>Shares</b></td>
<td valign="bottom"> </td>
<td valign="bottom"> </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>Weighted-<br />
average<br />
exercise<br />
price<br />
per share</b></td>
<td valign="bottom"> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Outstanding at December 31, 2013</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">3,958</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"> </td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">5.21</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Granted</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">937</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"> </td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">23.66</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Exercised</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">(691</td>
<td valign="bottom" nowrap="nowrap">) </td>
<td valign="bottom"> </td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">2.90</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Canceled or forfeited</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">(92</td>
<td valign="bottom" nowrap="nowrap">) </td>
<td valign="bottom"> </td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">14.98</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Outstanding at June 30, 2014</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">4,112</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt"> </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">9.59</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Exercisable at June 30, 2014</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">1,383</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt"> </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">3.61</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Vested and expected to vest at June 30, 2014</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">4,058</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt"> </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">9.64</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
</table>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%">
Options exercisable for 691 shares of common stock were exercised
during the six months ended June 30, 2014, resulting in total
proceeds to the Company of $1,864. In accordance with the stock
option plans, the shares were issued from a pool of shares reserved
for issuance under the stock option plans described above.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt">
<b><i>Employee stock purchase plan</i></b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
On June 3, 2013, the Company’s board of directors
adopted its 2013 Employee Stock Purchase Plan (“2013
ESPP”), which was subsequently approved by its stockholders
and became effective upon the closing of the Company’s
initial public offering on June 24, 2013. The 2013 ESPP
authorizes the initial issuance of up to a total of 238 shares of
the Company’s common stock to participating employees. The
first offering period under the 2013 ESPP opened on August 1,
2014.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt">
<b><i>Warrants</i></b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
As of June 30, 2014 and December 31, 2013, the Company
had 338 warrants outstanding to purchase common stock. During the
three and six months ended June 30, 2014, there were no
warrants exercised and no cancellations or expirations.</p>
</div>
<div>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt">
<b><i>Recent accounting pronouncements</i></b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
During the quarter ended June 30, 2014, the FASB issued ASU
No. 2014-09, Revenue from Contracts with Customers (“ASU
No. 2014-09”), which supersedes all existing revenue
recognition requirements, including most industry-specific
guidance. The new standard requires a company to recognize revenue
when it transfers goods or services to customers in an amount that
reflects the consideration that the company expects to receive for
those goods or services. The new standard will be effective on
January 1, 2017 and early adoption is not permitted for public
entities. The Company is currently evaluating the potential impact
that ASU No. 2014-09 may have on its financial position and
results of operations.</p>
</div>
1
<div>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt">
<b>4. Commitments and contingencies</b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
On June 3, 2013, the Company entered into a nine-year building
lease for approximately 43,600 square feet of space for its new
corporate headquarters at 150 Second Street, Cambridge,
Massachusetts, which commenced in December 2013. The lease has
monthly lease payments of $209 the first 12 months with annual rent
escalations thereafter and provided a rent abatement of $209 per
month for the first six months. The Company has the option to
extend this lease by an additional five years. As the Company
obtained access to the newly leased space on July 22, 2013 in
order to begin the build-out, this is considered the lease
commencement date for accounting purposes, thus rent expense began
on this date and is recognized on a straight-line basis over the
term of the lease. In addition, the lease provided a contribution
from the landlord towards the initial build-out of the space of up
to $6,538. The Company capitalizes the leasehold improvements as
property and equipment and records the landlord incentive payments
received as deferred rent and amortizes these amounts as reductions
to rent expense over the lease term. In accordance with the lease,
the Company entered into a cash-collateralized irrevocable standby
letter of credit in the amount of $1,253, naming the landlord as
beneficiary. This letter of credit may be reduced to $1,044, $835,
and $627 upon the rent commencement date and the first and second
anniversaries of the rent commencement date, respectively. The
Company relocated into its new corporate headquarters in December
2013 and ceased use of its former facility during the first quarter
of 2014. During the first quarter of 2014, the Company fully
subleased its former facility, which decreased the rent abatement
available under its new lease. The lease for the Company’s
former headquarters, located at 840 Memorial Drive, Cambridge,
Massachusetts, expires on March 31, 2015.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%">
On June 9, 2014, the Company amended its lease agreement to
add an additional 9,869 square feet of space for its corporate
headquarters at 150 Second Street, Cambridge, Massachusetts. The
expansion increases the monthly lease payments by $47 beginning in
September 2014 with rent escalations thereafter. In addition, the
lease amendment provides a contribution from the landlord towards
the build-out of the additional space of up to $1,234.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%">
The Company is party to various agreements, principally relating to
licensed technology, that require future payments relating to
milestones not met at June 30, 2014 and December 31, 2013
or royalties on future sales of specified products.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%">
The Company enters into standard indemnification agreements in the
ordinary course of business. Pursuant to the agreements, the
Company indemnifies, holds harmless, and agrees to reimburse the
indemnified party for losses suffered or incurred by the
indemnified party, generally the Company’s business partners
or customers, in connection with claims by any third party with
respect to the Company’s products or business activities. The
term of these indemnification agreements is generally perpetual any
time after execution of the agreement. The maximum potential amount
of future payments the Company could be required to make under
these indemnification agreements is unlimited. The Company has
never incurred costs to defend lawsuits or settle claims related to
these indemnification agreements.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%">
The Company’s wholly-owned subsidiary bluebird bio France
– SARL participates in the French Crédit
d’Impôt Recherche (“CIR”) program which
allows companies to monetize up to 30% of eligible research
expenses. The Company received aggregate reimbursement of $807
related to years 2010 through 2012. The Company recognized these
amounts as reductions to research and development expense in the
periods incurred. The years 2010 through 2013 are open and subject
to examination. The Company has applied for $873 related to 2013,
which is classified as current assets and has not yet applied for
$566 related to the six months ended June 30, 2014 which are
classified as non-current assets within the condensed consolidated
balance sheets as of June 30, 2014. The Company received a
notice from the Ministère de l’Enseignement
Supérieur et de la Recherche in March 2014 inquiring of the
Company regarding the eligibility of such research expenses
pursuant to the CIR program. Based on the nature of the research
activities conducted by bluebird bio France, SARL, the Company has
concluded that it is probable that these receivables are
collectable. However, any adjustment as a result of the inquiry
would result in a refund of the amounts previously received or
impairment of the Company’s receivable.</p>
<p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 1px; MARGIN-TOP: 12px">
 </p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 0pt; TEXT-INDENT: 4%">
In June 2014, the Company acquired Pregenen. The Company may be
required to make up to an additional $135,000 in future contingent
cash payments upon the achievement of certain preclinical, clinical
and commercial milestones related to the Pregenen technology, of
which $15,000 relates to preclinical milestones, $20,100 relates to
clinical milestones and $99,900 relates to commercial milestones.
In accordance with accounting for business combinations guidance,
contingent consideration liabilities are required to be recognized
on the condensed consolidated balance sheets at fair value.
Estimating the fair value of contingent consideration requires the
use of significant assumptions primarily relating to probabilities
of successful achievement of certain preclinical, clinical and
commercial milestones, the expected timing in which these
milestones will be achieved and discount rates. The use of
different assumptions could result in materially different
estimates of fair value. See Note 3, “Fair value
measurements,” and Note 6, “Business
combinations,” for additional information.</p>
</div>
<div>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt">
<b><i>Business combinations</i></b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
On June 30, 2014, the Company completed its acquisition of
Pregenen for total consideration of $30,991, consisting of cash
consideration of $5,093, common stock consideration of $19,348 and
contingent consideration with an estimated fair value of $6,550.
The estimated fair value of the contingent consideration is based
upon significant assumptions regarding probabilities of successful
achievement of related milestones, the estimated timing in which
the milestones are achieved and discount rates. The estimated fair
value could materially differ from actual values or fair values
determined using different assumptions. See Note 3, “Fair
value measurements,” for additional information.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%">
This transaction was accounted for as a business combination under
the acquisition method of accounting. Accordingly, the tangible
assets and identifiable intangible assets acquired and liabilities
assumed were recorded at fair value as of the date of acquisition,
with the remaining purchase price recorded as goodwill. The
estimated fair values of the assets acquired and liabilities
assumed at the date of acquisition are summarized in Note 6,
“Business combinations.” The estimated fair values of
acquired assets and assumed liabilities were determined using the
methods discussed in the following paragraphs and require
significant judgment and estimates, which could materially differ
from actual values and fair values determined using different
methods or assumptions.</p>
<p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 1px; MARGIN-TOP: 12px">
 </p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 0pt; TEXT-INDENT: 4%">
The purchase price allocation was initially prepared on a
preliminary basis and is subject to change as additional
information becomes available concerning the fair value and tax
basis of the assets acquired and liabilities assumed and contingent
consideration. Any adjustments to the purchase price allocations
are made as soon as practicable but no later than one year from the
acquisition date.</p>
</div>
<div>
<p style="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">
<b>5. Significant agreements</b></p>
<p style="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">
<b><i>Celgene Corporation</i></b></p>
<p style="margin-top:6pt; margin-bottom:0pt; margin-left:4%; font-size:10pt; font-family:Times New Roman">
<i>Summary of the Collaboration Agreement</i></p>
<p style="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">
On March 19, 2013, the Company entered into a Master
Collaboration Agreement (the “Collaboration Agreement”)
with Celgene to discover, develop and commercialize potentially
disease-altering gene therapies in oncology. The collaboration is
focused on applying gene therapy technology to genetically modify a
patient’s own T cells, known as chimeric antigen receptor, or
CAR, T cells, to target and destroy cancer cells. Additionally, on
March 19, 2013, the Company entered into a Platform Technology
Sublicense Agreement (the “Sublicense Agreement”) with
Celgene pursuant to which the Company obtained a sublicense to
certain intellectual property from Celgene, originating under
Celgene’s license from Baylor College of Medicine, for use in
the collaboration.</p>
<p style="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">
Under the terms of the Collaboration Agreement, the Company
received a $75,000 up-front, non-refundable cash payment. The
Company will be responsible for conducting discovery, research and
development activities through completion of Phase I clinical
studies, if any, during the initial term of the agreement, or three
years. The collaboration is governed by a joint steering committee
(“JSC”) formed by an equal number of representatives
from the Company and Celgene. The JSC will, among other activities,
review the collaboration program, review and evaluate product
candidates and approve regulatory plans. In addition to the JSC,
the Collaboration Agreement provides that the Company and Celgene
each appoint representatives to a patent committee, which is
responsible for managing the intellectual property developed and
used during the collaboration.</p>
<p style="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">
Prior to expiration of the initial term of the Collaboration
Agreement, Celgene has two options to extend the term, through
March 19, 2019, with the payment of significant extension
fees. Separately, Celgene has an option to license an unlimited
number of product candidates resulting from the collaboration
during a period commencing upon execution of the Collaboration
Agreement and continuing through a specified period following the
completion of Phase I clinical studies for each individual product
candidate. In the event such option is exercised, the Company would
grant Celgene an exclusive worldwide license to develop and
commercialize such product candidate. Upon exercise of the option
to license a product candidate, Celgene is required to pay an
option fee, which is subject to reduction if the Company elects to
co-develop and co-promote such product candidate in the United
States. For any product candidates licensed by Celgene, the Company
may be responsible, at Celgene’s election, to continue
performing certain development activities contemplated as part of
the collaboration plan. If Celgene does not exercise its option
with respect to a product candidate prior to the expiration of the
applicable option period (each a “declined product
candidate”), then the Company has the right to develop the
product candidate outside the scope of the collaboration, subject
to a Celgene opt-in right to obtain a license to that declined
product candidate for significant additional cash consideration.
The opt-in right exists through a specified period following the
completion of a pivotal study for the specific declined product
candidate and functions in the same manner as the option to license
any other product candidates resulting from the collaboration.</p>
<p style="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">
In addition, Celgene would be required to make certain milestone
payments upon the achievement of specified clinical, regulatory and
commercial events. For each product candidate that is licensed by
Celgene, the Company would be eligible to receive per product up to
$20,000 in option fees, up to $10,000 in clinical milestone
payments, up to $117,000 in regulatory milestone payments and up to
$78,000 in commercial milestone payments. Clinical milestone
payments are triggered upon initiation of a defined phase of
clinical research for a product candidate. Regulatory milestone
payments are triggered upon approval to market a product candidate
by the FDA or other global regulatory authorities. Commercial
milestone payments are triggered upon the first commercial sale of
an approved pharmaceutical product and when an approved
pharmaceutical product reaches certain defined levels of net sales
by the licensee or receives approval to be marketed by certain
global regulatory authorities in a specified number of countries
outside of the United States. In addition, to the extent any of the
product candidates licensed by Celgene are commercialized, the
Company would be entitled to receive tiered royalty payments
ranging from the mid-single digits to mid-teens based on a
percentage of net sales. Royalty payments are subject to certain
reductions, including for any royalty payments required to be made
by Celgene to acquire patent rights, with an aggregate minimum
floor. The Company is not eligible to receive either milestone
payments or royalty payments unless and until Celgene exercises its
option to license a product candidate resulting from the
collaboration whereupon the parties will execute a license
agreement, the terms of which are included as part of the
collaboration arrangement.</p>
<p style="font-size:1px;margin-top:12px;margin-bottom:0px">
 </p>
<p style="margin-top:0pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">
Additionally, the Company may elect to co-develop and co-promote
product candidates licensed by Celgene. If the Company elects to
co-develop and co-promote a product candidate, then the parties
would share equally in all costs incurred relating to the
development, commercialization and manufacture of the product
candidate within the United States and share equally in the profits
generated by such product candidate in the United States.
Additionally, if the Company elects to co-develop and co-promote a
product candidate, then the option fees, milestones and royalties
would decrease compared to those described above. Under this
scenario, the Company would receive per product up to $10,000 in
option fees, up to $10,000 in clinical milestone payments and
outside of the United States, up to $54,000 in regulatory milestone
payments and up to $36,000 in commercial milestone payments.
Clinical milestone payments are triggered upon initiation of a
defined phase of clinical research for a product candidate.
Regulatory milestone payments are triggered upon approval to market
a product candidate by global regulatory authorities. Commercial
milestone payments are triggered when an approved pharmaceutical
product reaches certain defined levels of net sales by the licensee
or receives approval to be marketed by certain global regulatory
authorities in a specified number of countries outside the United
States. In addition, to the extent any of the product candidates
licensed by Celgene and co-developed and co-promoted by the Company
are commercialized, the Company would be entitled to receive tiered
royalty payments ranging from the mid-single digits to mid-teens
based on a percentage of net sales from sales generated outside of
the United States. Royalty payments are subject to certain
reductions, including for any royalty payments required to be made
by Celgene to acquire patent rights, with an aggregate minimum
floor. The Company is not eligible to receive profit share
payments, milestone payments or royalty payments unless and until
Celgene exercises its option to license a product candidate
resulting from the collaboration whereupon the parties will execute
a co-development, co-promote and profit share agreement, the terms
of which are included as part of the collaboration arrangement.</p>
<p style="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">
In the event Celgene elects to license a product candidate
discovered and developed as part of the Collaboration Agreement,
Celgene would be solely responsible for all costs and expenses of
manufacturing and supplying any product candidates. Subject to
customary back-up supply rights granted to Celgene, the Company has
the sole right to manufacture or have manufactured supplies of
vectors and associated payloads manufactured for incorporation into
the associated product candidate. Celgene would reimburse the
Company for the costs incurred to manufacture and supply such
vectors and associated payloads, plus a modest mark-up. The Company
is not obligated to manufacture or have manufactured supplies of
vectors and associated payloads for incorporation into an optioned
product candidate unless and until Celgene exercises its option to
license a product candidate resulting from the collaboration
whereupon the parties will execute a separate manufacturing and
supply agreement.</p>
<p style="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">
The Collaboration Agreement may be terminated by either the Company
or Celgene, upon written notice, in the event of the other
party’s uncured material breach. Celgene may terminate the
Collaboration Agreement for any reason upon written notice to the
Company. If the Collaboration Agreement is terminated, rights to
product candidates in development at the time of such termination
will be allocated to the parties through a mechanism included in
the Collaboration Agreement. In addition, if Celgene terminates the
Collaboration Agreement as a result of a breach by the Company,
then any then-existing co-development and co-promotion agreement
will be automatically terminated and replaced with a license
agreement for such product candidate and any amounts payable by
Celgene under any then-existing product license agreements will be
reduced.</p>
<p style="margin-top:18pt; margin-bottom:0pt; margin-left:4%; font-size:10pt; font-family:Times New Roman">
<i>Call Option</i></p>
<p style="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">
During the initial three-year term of the collaboration and, if
extended, during the first two-year extension term of the
collaboration, in the event that the Company engages in a change in
control transaction, including for such purposes a merger or
consolidation of the Company or the sale of all or substantially
all of the Company’s assets, or if another person or entity
or group of persons or entities acquires at least 50% of the
Company’s voting capital stock, then Celgene has the right,
but not the obligation, to terminate the Collaboration Agreement
and obtain perpetual, non-terminable, worldwide, exclusive, fully
paid-up licenses to all, but not less than all, of the product
candidates previously identified under the Collaboration Agreement
(the “Call Option”). Under the Call Option, the product
candidates to which Celgene would have the right to acquire
licenses include any product candidate previously licensed out of
the collaboration during the term of the collaboration, any product
candidate for which the Company has exercised the right to
co-develop and co-promote within the United States, any product
candidate for which Celgene previously declined its option to
obtain a license and any product candidate for which at least <i>in
vivo</i> efficacy studies have been initiated or authorized by the
JSC. The purchase price for such licenses would be based on the
fair value of these rights received and obligations assumed
determined pursuant to a binding arbitration process.</p>
<p style="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">
In addition, during the initial three-year term of the
collaboration, but not during any extension term, in the event that
Celgene exercises the Call Option, in addition to the right to
acquire the fully paid-up licenses described above, Celgene would
obtain a perpetual, non-terminable, worldwide, exclusive license to
the Company’s intellectual property to develop one or more
CAR T cell products targeting one or more oncology associated
target antigens for the remainder of the initial collaboration
term. Following the initial collaboration term, the license to the
Company’s intellectual property is limited to target antigens
identified by Celgene promptly following the initial collaboration
term for which Celgene reasonably intends to develop CAR T cell
products. There is no limit to the number of oncology-related
target antigens Celgene may select under this license. Upon
commercialization of any such product candidate so licensed by
Celgene, Celgene would be obligated to pay the Company a specified
milestone payment upon regulatory approval and a percentage of net
sales as a royalty.</p>
<p style="font-size:1px;margin-top:12px;margin-bottom:0px">
 </p>
<p style="margin-top:0pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">
The Company concluded that the value of the Call Option is
immaterial based primarily on the probability that the Call Option
would become exercisable.</p>
<p style="margin-top:18pt; margin-bottom:0pt; margin-left:4%; font-size:10pt; font-family:Times New Roman">
<i>Accounting Analysis</i></p>
<p style="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">
The Company’s arrangement with Celgene contains the following
deliverables: (i) discovery, research and development
services, (ii) participation on the JSC and
(iii) participation on the patent committee. The Company has
determined that the options to extend the term of the agreement and
the options to license product candidates, including those related
to Celgene’s opt-in right for a declined product candidate,
are substantive options. Celgene is not contractually obligated to
exercise the options. Additionally, as a result of the uncertain
outcome of the discovery, research and development activities, the
Company is at risk with regard to whether Celgene will exercise the
options. Moreover, the Company has determined that the options are
not priced at a significant and incremental discount. Accordingly,
the options are not considered deliverables at the inception of the
arrangement and the associated option fees are not included in
allocable arrangement consideration. The Company has determined
that the potential obligation to manufacture or have manufactured
supplies of vectors and associated payloads for incorporation into
an optioned product candidate is contingent upon Celgene exercising
its option to license a product candidate resulting from the
collaboration. Therefore, consistent with the treatment of the
options to license product candidates, the Company’s
potential obligation under a manufacturing and supply agreement is
not considered a deliverable at the inception of the arrangement
and the associated fees are not included in allocable arrangement
consideration.</p>
<p style="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">
The Company concluded that each of the three deliverables
identified at the inception of the arrangement (discovery, research
and development services, participation on the JSC and
participation on the patent committee) has standalone value from
the other undelivered elements. Additionally, the Collaboration
Agreement does not include return rights related to the initial
collaboration term. Accordingly, each deliverable qualifies as a
separate unit of accounting.</p>
<p style="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">
The Company identified the allocable arrangement consideration as
the $75,000 up-front payment. The Company determined that each of
the identified deliverables have the same period of performance
(the three year initial term) and have the same pattern of revenue
recognition, ratably over the period of performance. As a result,
the $75,000 arrangement consideration will be recognized over the
three year initial term.</p>
<p style="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">
The Company evaluated all of the milestones that may be received in
connection with Celgene’s option to license a product
candidate resulting from the collaboration. In evaluating if a
milestone is substantive, the Company assesses whether:
(i) the consideration is commensurate with either the
Company’s performance to achieve the milestone or the
enhancement of the value of the delivered item(s) as a result of a
specific outcome resulting from the Company’s performance to
achieve the milestone, (ii) the consideration relates solely
to past performance and (iii) the consideration is reasonable
relative to all of the deliverables and payment terms within the
arrangement. All clinical and regulatory milestones are considered
substantive on the basis of the contingent nature of the milestone,
specifically reviewing factors such as the scientific, clinical,
regulatory, commercial and other risks that must be overcome to
achieve the milestone as well as the level of effort and investment
required. Accordingly, such amounts will be recognized as revenue
in full in the period in which the associated milestone is
achieved, assuming all other revenue recognition criteria are met.
All commercial milestones will be accounted for in the same manner
as royalties and recorded as revenue upon achievement of the
milestone, assuming all other revenue recognition criteria are
met.</p>
<p style="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">
During the three and six months ended June 30, 2014, the
Company recognized $6,250 and $12,500, respectively, of revenue
associated with its collaboration with Celgene related to the
recognition of discovery, research and development services. As of
June 30, 2014, there was $42,708 of deferred revenue related
to the Company’s collaboration with Celgene which is
classified as current or non-current in the condensed consolidated
balance sheets based on the contractual term of the
arrangement.</p>
<p style="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">
<b><i>Association Française contre les Myopathies</i></b></p>
<p style="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">
In January 2011, the Company entered into a research funding
agreement with the Association Française contre les Myopathies
(“AFM”), a nonprofit organization dedicated to curing
rare neuromuscular diseases and providing treatments to reduce the
associated disabilities of such diseases. As part of the agreement,
AFM funded the Company 1,000 Euros to be used to advance the
Company’s research, process development, manufacturing,
preclinical development, and clinical development in gene therapy
for beta-hemoglobinopathies in ß-thalassemia and/or in Sickle
Cell Disease.</p>
<p style="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">
The funding, or a portion thereof depending on timing, shall be
repaid to AFM upon any of the following events: (i) upon
out-licensing or sale of the program, (ii) upon obtaining the
first product authorization for the market, or (iii) upon sale
of the Company, provided that development of the program is active
at the time of such sale. The agreement is for a period of four
years. The Company believes that repayment of the funds paid under
the agreement is not probable as of the date of the agreement,
June 30, 2014 or December 31, 2013. The Company
recognizes the revenue under this arrangement on a straight-line
basis over the term of the agreement and will reassess the
probability of repayment at the end of each reporting period.</p>
</div>
<div>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
The following table summarizes the stock option activity under the
Company’s equity award plans:</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 12pt; MARGIN-TOP: 0pt">
 </p>
<table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="76%" align="center" border="0">
<tr>
<td width="81%"></td>
<td valign="bottom" width="5%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="5%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman">
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>Shares</b></td>
<td valign="bottom"> </td>
<td valign="bottom"> </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>Weighted-<br />
average<br />
exercise<br />
price<br />
per share</b></td>
<td valign="bottom"> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Outstanding at December 31, 2013</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">3,958</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"> </td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">5.21</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Granted</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">937</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"> </td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">23.66</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Exercised</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">(691</td>
<td valign="bottom" nowrap="nowrap">) </td>
<td valign="bottom"> </td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">2.90</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Canceled or forfeited</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">(92</td>
<td valign="bottom" nowrap="nowrap">) </td>
<td valign="bottom"> </td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">14.98</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Outstanding at June 30, 2014</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">4,112</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt"> </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">9.59</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Exercisable at June 30, 2014</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">1,383</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt"> </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">3.61</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Vested and expected to vest at June 30, 2014</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">4,058</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt"> </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">9.64</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
</table>
</div>
<div>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
The following table sets forth the Company’s assets and
liabilities that are measured at fair value on a recurring basis as
of June 30, 2014 and December 31, 2013:</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 12pt; MARGIN-TOP: 0pt">
 </p>
<table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="92%" align="center" border="0">
<tr>
<td width="61%"></td>
<td valign="bottom" width="5%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="5%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="5%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="5%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman">
<td valign="bottom" nowrap="nowrap">
<p style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman; BORDER-BOTTOM: #000000 1pt solid; WIDTH: 39.5pt">
<b>Description</b></p>
</td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>Total</b></td>
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>Quoted<br />
prices in<br />
active<br />
markets</b><br />
<b>(Level 1)</b></td>
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>Significant<br />
other<br />
observable<br />
inputs</b><br />
<b>(Level 2)</b></td>
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>Significant<br />
unobservable<br />
inputs</b><br />
<b>(Level 3)</b></td>
<td valign="bottom"> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
<b>June 30, 2014</b></p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Assets:</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Cash and cash equivalents</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">175,710</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">175,710</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom" nowrap="nowrap">$</td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom" nowrap="nowrap">$</td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 5em; TEXT-INDENT: -1em">
Total assets</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">175,710</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">175,710</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom" nowrap="nowrap">$</td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom" nowrap="nowrap">$</td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Liabilities:</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Contingent consideration</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">6,550</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom" nowrap="nowrap">$</td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom" nowrap="nowrap">$</td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">6,550</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 5em; TEXT-INDENT: -1em">
Total liabilities</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">6,550</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom" nowrap="nowrap">$</td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom" nowrap="nowrap">$</td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">6,550</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
<b>December 31, 2013</b></p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Total cash and cash equivalents</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">206,279</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">206,279</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom" nowrap="nowrap">$</td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom" nowrap="nowrap">$</td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
</div>
<div>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt">
<b><i>Intangible assets</i></b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
Intangible assets consist of acquired core technology with finite
lives. The Company amortizes its intangible assets using the
straight-line method over their estimated economic lives. The
Company evaluates the potential impairment of intangible assets if
events or changes in circumstances indicate that the carrying
amount of the assets may not be fully recoverable or that the
useful lives of these assets are no longer appropriate. The
impairment test is based on a comparison of the undiscounted cash
flows expected to be generated from the use of the asset group and
its eventual disposition to the carrying value of the asset group.
If impairment is indicated, the asset is written down by the amount
by which the carrying value of the asset exceeds the related fair
value of the asset. The Company has not recognized an impairment
charge related to intangible assets.</p>
</div>
<div>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 0pt; TEXT-INDENT: 4%">
The estimated amortization of intangible assets for the year ended
December 31, 2014 and for each of the five succeeding years
and thereafter is as follows:</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 12pt; MARGIN-TOP: 0pt">
 </p>
<table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="68%" align="center" border="0">
<tr>
<td width="88%"></td>
<td valign="bottom" width="6%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
2014</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">1,881</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
2015</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">3,763</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
2016</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">3,763</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
2017</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">3,763</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
2018</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">3,763</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
2019 and thereafter</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">13,167</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Total</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">30,100</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
</div>
<div>
<p style="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">
<b>1. Description of the business</b></p>
<p style="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">
bluebird bio, Inc. (the “Company” or
“bluebird”) was incorporated in Delaware on
April 16, 1992, and is headquartered in Cambridge,
Massachusetts. The Company was formed to develop, manufacture and
market therapies to safely and effectively deliver genes useful in
the treatment of serious human diseases. Since its inception, the
Company has devoted substantially all of its resources to its
development efforts relating to its product candidates, including
activities to manufacture product in compliance with good
manufacturing practices (“GMP”), conduct clinical
studies of its product candidates, provide general and
administrative support for these operations and protect its
intellectual property.</p>
<p style="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">
On June 30, 2014, the Company acquired all of the outstanding
capital stock of Precision Genome Engineering, Inc.
(“Pregenen”) and in connection therewith, obtained the
rights to Pregenen’s gene editing and cell signaling
technology. See Note 6, “Business combinations,” for
additional information.</p>
</div>
<div>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%">
The following common stock equivalents were excluded from the
calculation of diluted net loss per share for the periods indicated
because including them would have had an anti-dilutive effect:</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 12pt; MARGIN-TOP: 0pt">
 </p>
<table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="92%" align="center" border="0">
<tr>
<td width="76%"></td>
<td valign="bottom" width="2%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="2%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="2%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="2%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman">
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="6" align="center"><b>Three months<br />
ended June 30,</b></td>
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="6" align="center"><b>Six months<br />
ended June 30,</b></td>
<td valign="bottom"> </td>
</tr>
<tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman">
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>2014</b></td>
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>2013</b></td>
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>2014</b></td>
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>2013</b></td>
<td valign="bottom"> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Warrants</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">338</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">440</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">338</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">440</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Outstanding stock options</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">4,112</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">3,890</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">4,112</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">3,890</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Unvested restricted stock</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">27</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">110</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">27</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">110</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Acquisition holdback (Note 6)</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">94</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom" nowrap="nowrap"> </td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">94</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom" nowrap="nowrap"> </td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top"></td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">4,571</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">4,440</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">4,571</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">4,440</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
</div>
<div>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%">
The following table summarizes the estimated fair value of the
assets acquired and liabilities assumed at the date of
acquisition:</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 12pt; MARGIN-TOP: 0pt">
 </p>
<table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="68%" align="center" border="0">
<tr>
<td width="84%"></td>
<td valign="bottom" width="10%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman">
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>June 30, 2014</b></td>
<td valign="bottom"> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Cash</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">420</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Gene editing platform intangible asset</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">30,100</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Goodwill</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">13,128</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Other assets acquired</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">111</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Total assets acquired</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">43,759</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Deferred tax liabilities</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">11,797</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Other liabilities assumed</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">971</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Total liabilities assumed</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">12,768</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Net assets acquired</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">30,991</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
</div>
<div>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 0pt">
<b>3. Fair value measurements</b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
The following table sets forth the Company’s assets and
liabilities that are measured at fair value on a recurring basis as
of June 30, 2014 and December 31, 2013:</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 12pt; MARGIN-TOP: 0pt">
 </p>
<table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="92%" align="center" border="0">
<tr>
<td width="61%"></td>
<td valign="bottom" width="5%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="5%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="5%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="5%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman">
<td valign="bottom" nowrap="nowrap">
<p style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman; BORDER-BOTTOM: #000000 1pt solid; WIDTH: 39.5pt">
<b>Description</b></p>
</td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>Total</b></td>
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>Quoted<br />
prices in<br />
active<br />
markets</b><br />
<b>(Level 1)</b></td>
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>Significant<br />
other<br />
observable<br />
inputs</b><br />
<b>(Level 2)</b></td>
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>Significant<br />
unobservable<br />
inputs</b><br />
<b>(Level 3)</b></td>
<td valign="bottom"> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
<b>June 30, 2014</b></p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Assets:</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Cash and cash equivalents</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">175,710</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">175,710</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom" nowrap="nowrap">$</td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom" nowrap="nowrap">$</td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 5em; TEXT-INDENT: -1em">
Total assets</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">175,710</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">175,710</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom" nowrap="nowrap">$</td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom" nowrap="nowrap">$</td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Liabilities:</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Contingent consideration</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">6,550</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom" nowrap="nowrap">$</td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom" nowrap="nowrap">$</td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">6,550</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 5em; TEXT-INDENT: -1em">
Total liabilities</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">6,550</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom" nowrap="nowrap">$</td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom" nowrap="nowrap">$</td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">6,550</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
<b>December 31, 2013</b></p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Total cash and cash equivalents</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">206,279</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">206,279</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom" nowrap="nowrap">$</td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom" nowrap="nowrap">$</td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt">
<b><i>Cash and cash equivalents</i></b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
The Company considers all highly liquid securities with original
final maturities of three months or less from the date of purchase
to be cash equivalents. As of June 30, 2014 and
December 31, 2013, cash and cash equivalents comprise funds in
cash and money market accounts.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt">
<b><i>Contingent consideration</i></b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
In connection with the acquisition of Pregenen, the Company
recorded contingent consideration pertaining to the amounts
potentially payable to Pregenen’s former equityholders
pursuant to the Stock Purchase Agreement (the “Stock Purchase
Agreement”) by and among the Company, Pregenen and
Pregenen’s former equityholders. Contingent consideration is
measured at fair value and is based on significant inputs not
observable in the market, which represents a Level 3 measurement
within the fair value hierarchy. The valuation of contingent
consideration uses assumptions the Company believes would be made
by a market participant. The Company assesses these estimates on an
on-going basis as additional data impacting the assumptions is
obtained. Future changes in the fair value of contingent
consideration related to updated assumptions and estimates are
recognized within the condensed consolidated statements of
operations and comprehensive loss.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%">
Contingent consideration may change significantly as development
progresses and additional data are obtained, impacting the
Company’s assumptions regarding probabilities of successful
achievement of related milestones used to estimate the fair value
of the liability and the timing in which they are expected to be
achieved. In evaluating the fair value information, considerable
judgment is required to interpret the market data used to develop
the estimates. The estimates of fair value may not be indicative of
the amounts that could be realized in a current market exchange.
Accordingly, the use of different market assumptions and/or
different valuation techniques could result in materially different
fair value estimates.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%">
The significant unobservable inputs used in the measurement of fair
value of the Company’s contingent consideration are
probabilities of successful achievement of preclinical, clinical
and commercial milestones, the period in which these milestones are
expected to be achieved ranging from 2015 to 2026 and discount
rates ranging from 10% to 15%. Significant increases or decreases
in any of the probabilities of success would result in a
significantly higher or lower fair value measurement, respectively.
Significant increases or decreases in these other inputs would
result in a significantly lower or higher fair value measurement,
respectively.</p>
<p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 1px; MARGIN-TOP: 12px">
 </p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 0pt; TEXT-INDENT: 4%">
The table below provides a roll-forward of fair value of the
Company’s contingent consideration obligations which include
Level 3 inputs:</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 12pt; MARGIN-TOP: 0pt">
 </p>
<table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="68%" align="center" border="0">
<tr>
<td width="81%"></td>
<td valign="bottom" width="14%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman">
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>Six months ended<br />
June 30, 2014</b></td>
<td valign="bottom"> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Beginning balance</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom" nowrap="nowrap">$</td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Additions</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">6,550</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Changes in fair value</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom" nowrap="nowrap"> </td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Payments</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom" nowrap="nowrap"> </td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Ending balance</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">6,550</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%">
As of June 30, 2014, $453 of the fair value of the
Company’s total contingent consideration obligations was
reflected as components of accrued expenses and other current
liabilities within the condensed consolidated balance sheets with
the remaining balances reflected as a non-current liability.</p>
</div>
<div>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt">
<b>2. Summary of significant accounting policies and basis of
presentation</b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt">
<b><i>Basis of presentation and principles of
consolidation</i></b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
The accompanying condensed consolidated financial statements are
unaudited and have been prepared by the Company in accordance with
accounting principles generally accepted in the United States
(“GAAP”) as found in the Accounting Standards
Codification (“ASC”) and Accounting Standards Update
(“ASU”) of the Financial Accounting Standards Board
(“FASB”). Certain information and footnote disclosures
normally included in the Company’s annual financial
statements have been condensed or omitted. These interim condensed
consolidated financial statements, in the opinion of management,
reflect all normal recurring adjustments necessary for a fair
presentation of the Company’s financial position and results
of operations for the interim periods ended June 30, 2014 and
2013.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%">
The results of operations for the interim periods are not
necessarily indicative of the results of operations to be expected
for the full year. These interim financial statements should be
read in conjunction with the audited financial statements as of and
for the year ended December 31, 2013, and the notes thereto,
which are included in the Company’s Annual Report on Form
10-K filed with the Securities and Exchange Commission (the
“SEC”) on March 5, 2014.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%">
The accompanying condensed consolidated financial statements
include the accounts of the Company and its wholly-owned
subsidiaries, Precision Genome Engineering, Inc., bluebird bio
France – SARL, bluebird bio Australia Pty Ltd. and bluebird
bio Securities Corporation. All intercompany balances and
transactions have been eliminated in consolidation. The assets
acquired and liabilities assumed in connection with the
Company’s acquisition of Pregenen were recorded at their fair
values as of June 30, 2014, the date of the acquisition, and
the operating results of Pregenen have been consolidated with those
of the Company from the date of acquisition. Any reference in these
notes to applicable guidance is meant to refer to GAAP. The Company
views its operations and manages its business in one operating
segment. All material long-lived assets of the Company reside in
the United States.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt">
<b><i>Summary of accounting policies</i></b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
The significant accounting policies described in the
Company’s audited financial statements as of and for the year
ended December 31, 2013, and the notes thereto, which are
included in the Annual Report on Form 10-K, have had no material
changes during the six months ended June 30, 2014, except as
noted below:</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt">
<b><i>Business combinations</i></b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
On June 30, 2014, the Company completed its acquisition of
Pregenen for total consideration of $30,991, consisting of cash
consideration of $5,093, common stock consideration of $19,348 and
contingent consideration with an estimated fair value of $6,550.
The estimated fair value of the contingent consideration is based
upon significant assumptions regarding probabilities of successful
achievement of related milestones, the estimated timing in which
the milestones are achieved and discount rates. The estimated fair
value could materially differ from actual values or fair values
determined using different assumptions. See Note 3, “Fair
value measurements,” for additional information.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%">
This transaction was accounted for as a business combination under
the acquisition method of accounting. Accordingly, the tangible
assets and identifiable intangible assets acquired and liabilities
assumed were recorded at fair value as of the date of acquisition,
with the remaining purchase price recorded as goodwill. The
estimated fair values of the assets acquired and liabilities
assumed at the date of acquisition are summarized in Note 6,
“Business combinations.” The estimated fair values of
acquired assets and assumed liabilities were determined using the
methods discussed in the following paragraphs and require
significant judgment and estimates, which could materially differ
from actual values and fair values determined using different
methods or assumptions.</p>
<p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 1px; MARGIN-TOP: 12px">
 </p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 0pt; TEXT-INDENT: 4%">
The purchase price allocation was initially prepared on a
preliminary basis and is subject to change as additional
information becomes available concerning the fair value and tax
basis of the assets acquired and liabilities assumed and contingent
consideration. Any adjustments to the purchase price allocations
are made as soon as practicable but no later than one year from the
acquisition date.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt">
<b><i>Goodwill</i></b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
Goodwill represents the excess of the purchase price over the fair
value of the net assets acquired when accounted for using the
acquisition method of accounting for business combinations.
Goodwill is not amortized but is evaluated for impairment within
the Company’s single reporting unit on an annual basis,
during the fourth quarter, or more frequently if an event occurs or
circumstances change that would more-likely-than-not reduce the
fair value of the Company’s reporting unit below its carrying
amount. The Company has not recognized any impairment charges
related to goodwill.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt">
<b><i>Intangible assets</i></b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
Intangible assets consist of acquired core technology with finite
lives. The Company amortizes its intangible assets using the
straight-line method over their estimated economic lives. The
Company evaluates the potential impairment of intangible assets if
events or changes in circumstances indicate that the carrying
amount of the assets may not be fully recoverable or that the
useful lives of these assets are no longer appropriate. The
impairment test is based on a comparison of the undiscounted cash
flows expected to be generated from the use of the asset group and
its eventual disposition to the carrying value of the asset group.
If impairment is indicated, the asset is written down by the amount
by which the carrying value of the asset exceeds the related fair
value of the asset. The Company has not recognized an impairment
charge related to intangible assets.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt">
<b><i>Contingent consideration</i></b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
Each reporting period, the Company revalues the contingent
consideration obligations associated with business combinations to
their fair value and record within operating expenses increases in
their fair value as contingent consideration expense and decreases
in the fair value as contingent consideration income. Changes in
contingent consideration result from changes in the assumptions
regarding probabilities of successful achievement of related
milestones, the estimated timing in which the milestones are
achieved and the discount rate used to estimate the fair value of
the liability. Contingent consideration may change significantly as
development of the Company’s clinical programs in certain
indications progress and additional data are obtained, impacting
the Company’s assumptions. The assumptions used in estimating
fair value require significant judgment. The use of different
assumptions and judgments could result in a materially different
estimate of fair value. See Note 3, “Fair value
measurements,” for additional information.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt">
<b><i>Use of estimates</i></b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
The preparation of financial statements in conformity with GAAP
requires management to make estimates and assumptions that affect
the reported amounts in the financial statements and accompanying
notes. Actual results could materially differ from those estimates.
Management considers many factors in selecting appropriate
financial accounting policies and controls, and in developing the
estimates and assumptions that are used in the preparation of these
financial statements. Management must apply significant judgment in
this process. In addition, other factors may affect estimates,
including: expected business and operational changes, sensitivity
and volatility associated with the assumptions used in developing
estimates, and whether historical trends are expected to be
representative of future trends. The estimation process often may
yield a range of potentially reasonable estimates of the ultimate
future outcomes and management must select an amount that falls
within that range of reasonable estimates. This process may result
in actual results differing materially from those estimated amounts
used in the preparation of the financial statements. Estimates are
used in the following areas, among others: acquisition-date fair
value and subsequent fair value estimates used to assess impairment
of long-lived assets, including goodwill and intangible assets,
contingent consideration, stock-based compensation expense, accrued
expenses, revenue and income taxes.</p>
<p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 1px; MARGIN-TOP: 18px">
 </p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 0pt">
<b><i>Fair value of financial instruments</i></b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
The Company is required to disclose information on all assets and
liabilities reported at fair value that enables an assessment of
the inputs used in determining the reported fair values. ASC 820,
<i>Fair Value Measurements and Disclosures</i>, establishes a
hierarchy of inputs used in measuring fair value that maximizes the
use of observable inputs and minimizes the use of unobservable
inputs by requiring that the observable inputs be used when
available. Observable inputs are inputs that market participants
would use in pricing the asset or liability based on market data
obtained from sources independent of the Company. Unobservable
inputs are inputs that reflect the Company’s assumptions
about the inputs that market participants would use in pricing the
asset or liability, and are developed based on the best information
available in the circumstances. The fair value hierarchy applies
only to the valuation inputs used in determining the reported fair
value of the investments and is not a measure of the investment
credit quality. The three levels of the fair value hierarchy are
described below:</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 4%; MARGIN-TOP: 6pt">
Level 1—Valuations based on unadjusted quoted prices in
active markets for identical assets or liabilities that the Company
has the ability to access at the measurement date.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 4%; MARGIN-TOP: 6pt">
Level 2—Valuations based on quoted prices for similar assets
or liabilities in markets that are not active or for which all
significant inputs are observable, either directly or
indirectly.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 4%; MARGIN-TOP: 6pt">
Level 3—Valuations that require inputs that reflect the
Company’s own assumptions that are both significant to the
fair value measurement and unobservable. To the extent that
valuation is based on models or inputs that are less observable or
unobservable in the market, the determination of fair value
requires more judgment. Accordingly, the degree of judgment
exercised by the Company in determining fair value is greatest for
instruments categorized in Level 3. A financial
instrument’s level within the fair value hierarchy is based
on the lowest level of any input that is significant to the fair
value measurement.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%">
The carrying amounts of accounts payable and accrued expenses
approximate their fair values due to their short-term
maturities.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt">
<b><i>Other Income and Expense</i></b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
In March 2014, the Company received an award of $306 of tax
incentives from the Massachusetts Life Sciences Center, which will
allow the Company to monetize approximately $276 of state research
and development tax credits. In exchange for these incentives, the
Company pledged to hire an incremental fifteen employees and to
maintain the additional headcount through at least
December 31, 2018. Failure to do so could result in the
Company being required to repay some or all of these incentives. As
the Company met the additional headcount during the quarter ended
June 30, 2014, the Company has deferred and is amortizing the
benefit of this monetization on a straight-line basis over the
five-year performance period.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt">
<b><i>Net Income (Loss) Per Share</i></b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
Basic net income (loss) per share is calculated by dividing net
income (loss) attributable to common stockholders by the weighted
average number of common shares outstanding during the period.
Diluted net income per share is calculated by dividing the net
income attributable to common stockholders by the weighted-average
number of common equivalent shares outstanding for the period,
including any dilutive effect from outstanding stock options,
unvested restricted stock, warrants, and acquisition holdback
shares using the treasury stock method.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt">
<b><i>Recent accounting pronouncements</i></b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
During the quarter ended June 30, 2014, the FASB issued ASU
No. 2014-09, Revenue from Contracts with Customers (“ASU
No. 2014-09”), which supersedes all existing revenue
recognition requirements, including most industry-specific
guidance. The new standard requires a company to recognize revenue
when it transfers goods or services to customers in an amount that
reflects the consideration that the company expects to receive for
those goods or services. The new standard will be effective on
January 1, 2017 and early adoption is not permitted for public
entities. The Company is currently evaluating the potential impact
that ASU No. 2014-09 may have on its financial position and
results of operations.</p>
</div>
<div>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 0pt">
<b><i>Restricted common stock</i></b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 12pt; MARGIN-TOP: 0pt">
 </p>
<table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="76%" align="center" border="0">
<tr>
<td width="74%"></td>
<td valign="bottom" width="10%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="10%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman">
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>Shares</b></td>
<td valign="bottom"> </td>
<td valign="bottom"> </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b><font style="WHITE-SPACE: nowrap">Weighted-average</font><br />
grant date<br />
fair value</b></td>
<td valign="bottom"> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Unvested balance at December 31, 2013</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">69</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"> </td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">0.95</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Granted</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom" nowrap="nowrap"> </td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"> </td>
<td valign="bottom" nowrap="nowrap"> </td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Vested</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">(42</td>
<td valign="bottom" nowrap="nowrap">) </td>
<td valign="bottom"> </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">0.95</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Forfeited</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom" nowrap="nowrap"> </td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"> </td>
<td valign="bottom" nowrap="nowrap"> </td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Unvested balance at June 30, 2014</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">27</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt"> </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">0.95</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
</div>
24312000
23.66
-23258000
<div>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 0pt; TEXT-INDENT: 4%">
The table below provides a roll-forward of fair value of the
Company’s contingent consideration obligations which include
Level 3 inputs:</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 12pt; MARGIN-TOP: 0pt">
 </p>
<table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="68%" align="center" border="0">
<tr>
<td width="81%"></td>
<td valign="bottom" width="14%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman">
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>Six months ended<br />
June 30, 2014</b></td>
<td valign="bottom"> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Beginning balance</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom" nowrap="nowrap">$</td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Additions</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">6,550</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Changes in fair value</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom" nowrap="nowrap"> </td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Payments</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom" nowrap="nowrap"> </td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Ending balance</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">6,550</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
</div>
<div>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 0pt">
<b>6. Business combinations</b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
On June 30, 2014, the Company completed its acquisition of
Pregenen, a privately-held biotechnology company, upon which
Pregenen became a wholly-owned subsidiary. As a result, the Company
obtained gene editing and cell signaling technology with a broad
range of potential therapeutic applications.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%">
Under the terms of the Stock Purchase Agreement, the Company
purchased all of Pregenen’s outstanding capital stock in
exchange for 405 unregistered shares of common stock and $5,093 in
cash. The consideration for the transaction also includes an
additional 94 shares of common stock that will be held for a period
of 18 months after the acquisition and may be used to settle
certain claims for indemnification for breaches or inaccuracies in
Pregenen’s representations and warranties, covenants, and
agreements and an additional 2 shares relating to a working capital
adjustment. The Stock Purchase Agreement also provides for up to
$135,000 in future contingent cash payments upon the achievement of
certain preclinical, clinical and commercial milestones related to
the Pregenen technology, of which $15,000 relates to preclinical
milestones, $20,100 relates to clinical milestones and $99,900
relates to commercial milestones.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%">
The acquisition-date fair value of the purchase consideration is as
follows:</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 12pt; MARGIN-TOP: 0pt">
 </p>
<table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="68%" align="center" border="0">
<tr>
<td width="88%"></td>
<td valign="bottom" width="6%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Cash</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">5,093</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Common stock</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">19,348</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Contingent consideration</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">6,550</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Total purchase consideration</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">30,991</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%">
Common stock in the table above is comprised of $15,636 in common
stock transferred, $3,630 in common stock that will be held back
for a period of 18 months and $82 related to a working capital
adjustment.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%">
The transaction was accounted for as a business combination under
the acquisition method of accounting. Accordingly, the tangible and
identifiable intangible assets acquired and liabilities assumed
were recorded at estimated fair value as of the date of
acquisition, with the remaining consideration transferred recorded
as goodwill.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%">
The following table summarizes the estimated fair value of the
assets acquired and liabilities assumed at the date of
acquisition:</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 12pt; MARGIN-TOP: 0pt">
 </p>
<table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="68%" align="center" border="0">
<tr>
<td width="84%"></td>
<td valign="bottom" width="10%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman">
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>June 30, 2014</b></td>
<td valign="bottom"> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Cash</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">420</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Gene editing platform intangible asset</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">30,100</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Goodwill</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">13,128</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Other assets acquired</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">111</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Total assets acquired</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">43,759</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Deferred tax liabilities</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">11,797</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Other liabilities assumed</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">971</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Total liabilities assumed</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">12,768</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Net assets acquired</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">30,991</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%">
The purchase price allocation has been prepared on a preliminary
basis and is subject to change as additional information becomes
available concerning the fair value and tax basis of the assets
acquired and liabilities assumed and contingent consideration. Any
adjustments to the purchase price allocation will be made as soon
as practicable, but no later than one year from June 30, 2014,
the acquisition date.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%">
The fair value of the gene editing platform intangible asset was
determined using a relief from royalty approach, including
assumptions of projected revenues and royalty rate in addition to a
discount rate of 15.5% applied to the projected cash flows. The
Company considers the intangible asset acquired to be developed
technology, as at the date of the acquisition it could be used the
way it is intended to be used in certain ongoing research and
development activities. The Company believes the assumptions are
representative of those a market participant would use in
estimating fair value. The gene editing platform intangible asset
will be amortized to research and development expense over its
expected useful life of approximately eight years.</p>
<p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 1px; MARGIN-TOP: 12px">
 </p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 0pt; TEXT-INDENT: 4%">
The estimated amortization of intangible assets for the year ended
December 31, 2014 and for each of the five succeeding years
and thereafter is as follows:</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 12pt; MARGIN-TOP: 0pt">
 </p>
<table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="68%" align="center" border="0">
<tr>
<td width="88%"></td>
<td valign="bottom" width="6%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
2014</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">1,881</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
2015</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">3,763</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
2016</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">3,763</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
2017</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">3,763</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
2018</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">3,763</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
2019 and thereafter</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">13,167</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Total</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">30,100</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%">
The deferred tax liabilities of $11,797 primarily relate to the tax
impact of future amortization or impairments associated with the
identified intangible asset, which is not deductible for tax
purposes. See Note 8 “Income taxes,” for additional
information.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%">
Goodwill is calculated as the difference between the
acquisition-date fair value of the consideration transferred and
the fair values of the assets acquired and liabilities assumed and
is not expected to be deductible for income tax purposes. Goodwill
is recorded as an indefinite-lived asset and is not amortized but
tested for impairment on an annual basis or when indications of
impairment exist. Among the factors which resulted in goodwill for
the Pregenen acquisition was the opportunity to recognize synergies
with the Company’s existing gene insertion platform and
deferred tax liabilities recognized in connection with the
acquisition.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%">
The Company incurred a total of $171 in transaction costs in
connection with the acquisition, which were included in general and
administrative expenses within the condensed consolidated
statements of operations and comprehensive loss for the three and
six months ended June 30, 2014.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%">
In connection with the acquisition, the Company issued 3 shares of
common stock to a former consultant of Pregenen and recognized $151
of expense within general and administrative expenses in the
condensed consolidated statements of operations and comprehensive
loss for the three and six months ended June 30, 2014.</p>
</div>
<div>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
Stock-based compensation expense by award type was as follows:</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 12pt; MARGIN-TOP: 0pt">
 </p>
<table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="92%" align="center" border="0">
<tr>
<td width="72%"></td>
<td valign="bottom" width="3%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="3%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="3%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="3%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman">
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="6" align="center"><b>Three months<br />
ended June 30,</b></td>
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="6" align="center"><b>Six months ended<br />
June 30,</b></td>
<td valign="bottom"> </td>
</tr>
<tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman">
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>2014</b></td>
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>2013</b></td>
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>2014</b></td>
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>2013</b></td>
<td valign="bottom"> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Stock options</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">2,335</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">1,623</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">4,812</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">2,262</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Restricted stock awards</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">16</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">34</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">31</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">56</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top"></td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">2,351</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">1,657</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">4,843</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">2,318</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
</div>
-0.50
2.90
937000
<div>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt">
<b>10. Subsequent events</b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
In July 2014, the Company sold 3,450 shares of common stock
(inclusive of 450 shares of common stock sold by the Company
pursuant to the full exercise of an overallotment option granted to
the underwriters in connection with the offering) through an
underwritten public offering at a price of $34.00 per share. The
aggregate net proceeds received by the Company from the offering
were $109,776, net of underwriting discounts and commissions and
estimated offering expenses payable by the Company of approximately
$7,524.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%">
In connection with the Pregenen acquisition, the number of shares
comprising the purchase price consideration was increased from 499
to 501 due to a working capital adjustment completed on
July 29, 2014. On July 30, 2014, the Company registered a
total of 505 shares of common stock issued or to be issued to the
former equityholders of Pregenen under the Securities Act of
1933.</p>
</div>
P3Y
2015-03-31
<div>
<p style="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">
<b>8. Income taxes</b></p>
<p style="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">
Deferred tax assets and deferred tax liabilities are recognized
based on temporary differences between the financial reporting and
tax basis of assets and liabilities using statutory rates. A
valuation allowance is recorded against deferred tax assets if it
is more likely than not that some or all of the deferred tax assets
will not be realized. Due to the uncertainty surrounding the
realization of the favorable tax attributes in future tax returns,
the Company has recorded a full valuation allowance against the
Company’s otherwise recognizable net deferred tax assets. The
Company has allocated its valuation allowance in accordance with
the provisions of ASC 740, <i>Income Taxes</i>, which resulted in a
current deferred tax asset of $3,106 and a non-current deferred tax
liability of $3,106 as of June 30, 2014.</p>
<p style="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">
As a result of the acquisition of Pregenen, the Company recorded
intangible assets for which there is no tax basis, resulting in a
deferred tax liability. The deferred tax liabilities can be used as
a source of income to realize the Company’s pre-existing
deferred tax assets, thereby resulting in a decrease to the
corresponding valuation allowance. The decrease in the valuation
allowance resulted in an $11,797 income tax benefit for the three
and six months ended June 30, 2014.</p>
</div>
92000
<div>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt">
<b><i>Summary of accounting policies</i></b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
The significant accounting policies described in the
Company’s audited financial statements as of and for the year
ended December 31, 2013, and the notes thereto, which are
included in the Annual Report on Form 10-K, have had no material
changes during the six months ended June 30, 2014, except as
noted below:</p>
</div>
<div>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 0pt">
<b>9. Net loss per share</b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%">
The following common stock equivalents were excluded from the
calculation of diluted net loss per share for the periods indicated
because including them would have had an anti-dilutive effect:</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 12pt; MARGIN-TOP: 0pt">
 </p>
<table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="92%" align="center" border="0">
<tr>
<td width="76%"></td>
<td valign="bottom" width="2%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="2%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="2%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="2%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman">
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="6" align="center"><b>Three months<br />
ended June 30,</b></td>
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="6" align="center"><b>Six months<br />
ended June 30,</b></td>
<td valign="bottom"> </td>
</tr>
<tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman">
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>2014</b></td>
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>2013</b></td>
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>2014</b></td>
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>2013</b></td>
<td valign="bottom"> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Warrants</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">338</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">440</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">338</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">440</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Outstanding stock options</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">4,112</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">3,890</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">4,112</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">3,890</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Unvested restricted stock</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">27</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">110</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">27</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">110</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Acquisition holdback (Note 6)</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">94</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom" nowrap="nowrap"> </td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">94</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom" nowrap="nowrap"> </td>
<td valign="bottom" nowrap="nowrap" align="right">
—  </td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top"></td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">4,571</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">4,440</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">4,571</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">4,440</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
</div>
691000
14.98
4571000
<div>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt">
<b><i>Use of estimates</i></b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
The preparation of financial statements in conformity with GAAP
requires management to make estimates and assumptions that affect
the reported amounts in the financial statements and accompanying
notes. Actual results could materially differ from those estimates.
Management considers many factors in selecting appropriate
financial accounting policies and controls, and in developing the
estimates and assumptions that are used in the preparation of these
financial statements. Management must apply significant judgment in
this process. In addition, other factors may affect estimates,
including: expected business and operational changes, sensitivity
and volatility associated with the assumptions used in developing
estimates, and whether historical trends are expected to be
representative of future trends. The estimation process often may
yield a range of potentially reasonable estimates of the ultimate
future outcomes and management must select an amount that falls
within that range of reasonable estimates. This process may result
in actual results differing materially from those estimated amounts
used in the preparation of the financial statements. Estimates are
used in the following areas, among others: acquisition-date fair
value and subsequent fair value estimates used to assess impairment
of long-lived assets, including goodwill and intangible assets,
contingent consideration, stock-based compensation expense, accrued
expenses, revenue and income taxes.</p>
</div>
<div>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt">
<b><i>Net Income (Loss) Per Share</i></b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
Basic net income (loss) per share is calculated by dividing net
income (loss) attributable to common stockholders by the weighted
average number of common shares outstanding during the period.
Diluted net income per share is calculated by dividing the net
income attributable to common stockholders by the weighted-average
number of common equivalent shares outstanding for the period,
including any dilutive effect from outstanding stock options,
unvested restricted stock, warrants, and acquisition holdback
shares using the treasury stock method.</p>
</div>
<div>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 0pt">
<b><i>Fair value of financial instruments</i></b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
The Company is required to disclose information on all assets and
liabilities reported at fair value that enables an assessment of
the inputs used in determining the reported fair values. ASC 820,
<i>Fair Value Measurements and Disclosures</i>, establishes a
hierarchy of inputs used in measuring fair value that maximizes the
use of observable inputs and minimizes the use of unobservable
inputs by requiring that the observable inputs be used when
available. Observable inputs are inputs that market participants
would use in pricing the asset or liability based on market data
obtained from sources independent of the Company. Unobservable
inputs are inputs that reflect the Company’s assumptions
about the inputs that market participants would use in pricing the
asset or liability, and are developed based on the best information
available in the circumstances. The fair value hierarchy applies
only to the valuation inputs used in determining the reported fair
value of the investments and is not a measure of the investment
credit quality. The three levels of the fair value hierarchy are
described below:</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 4%; MARGIN-TOP: 6pt">
Level 1—Valuations based on unadjusted quoted prices in
active markets for identical assets or liabilities that the Company
has the ability to access at the measurement date.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 4%; MARGIN-TOP: 6pt">
Level 2—Valuations based on quoted prices for similar assets
or liabilities in markets that are not active or for which all
significant inputs are observable, either directly or
indirectly.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 4%; MARGIN-TOP: 6pt">
Level 3—Valuations that require inputs that reflect the
Company’s own assumptions that are both significant to the
fair value measurement and unobservable. To the extent that
valuation is based on models or inputs that are less observable or
unobservable in the market, the determination of fair value
requires more judgment. Accordingly, the degree of judgment
exercised by the Company in determining fair value is greatest for
instruments categorized in Level 3. A financial
instrument’s level within the fair value hierarchy is based
on the lowest level of any input that is significant to the fair
value measurement.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%">
The carrying amounts of accounts payable and accrued expenses
approximate their fair values due to their short-term
maturities.</p>
</div>
Three months or less
12670000
-854000
-12135000
12500000
-23932000
344000
4673000
69000
-24001000
11797000
-12135000
4534000
170000
7674000
168000
36671000
11277000
1864000
1896000
643000
-12670000
4843000
1017000
-30569000
-9207000
-2702000
25394000
1896000
-11797000
<div>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt">
<b><i>Goodwill</i></b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
Goodwill represents the excess of the purchase price over the fair
value of the net assets acquired when accounted for using the
acquisition method of accounting for business combinations.
Goodwill is not amortized but is evaluated for impairment within
the Company’s single reporting unit on an annual basis,
during the fourth quarter, or more frequently if an event occurs or
circumstances change that would more-likely-than-not reduce the
fair value of the Company’s reporting unit below its carrying
amount. The Company has not recognized any impairment charges
related to goodwill.</p>
</div>
45000
<div>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt">
<b><i>Basis of presentation and principles of
consolidation</i></b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
The accompanying condensed consolidated financial statements are
unaudited and have been prepared by the Company in accordance with
accounting principles generally accepted in the United States
(“GAAP”) as found in the Accounting Standards
Codification (“ASC”) and Accounting Standards Update
(“ASU”) of the Financial Accounting Standards Board
(“FASB”). Certain information and footnote disclosures
normally included in the Company’s annual financial
statements have been condensed or omitted. These interim condensed
consolidated financial statements, in the opinion of management,
reflect all normal recurring adjustments necessary for a fair
presentation of the Company’s financial position and results
of operations for the interim periods ended June 30, 2014 and
2013.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%">
The results of operations for the interim periods are not
necessarily indicative of the results of operations to be expected
for the full year. These interim financial statements should be
read in conjunction with the audited financial statements as of and
for the year ended December 31, 2013, and the notes thereto,
which are included in the Company’s Annual Report on Form
10-K filed with the Securities and Exchange Commission (the
“SEC”) on March 5, 2014.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%">
The accompanying condensed consolidated financial statements
include the accounts of the Company and its wholly-owned
subsidiaries, Precision Genome Engineering, Inc., bluebird bio
France – SARL, bluebird bio Australia Pty Ltd. and bluebird
bio Securities Corporation. All intercompany balances and
transactions have been eliminated in consolidation. The assets
acquired and liabilities assumed in connection with the
Company’s acquisition of Pregenen were recorded at their fair
values as of June 30, 2014, the date of the acquisition, and
the operating results of Pregenen have been consolidated with those
of the Company from the date of acquisition. Any reference in these
notes to applicable guidance is meant to refer to GAAP. The Company
views its operations and manages its business in one operating
segment. All material long-lived assets of the Company reside in
the United States.</p>
</div>
<div>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt">
<b><i>Other Income and Expense</i></b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
In March 2014, the Company received an award of $306 of tax
incentives from the Massachusetts Life Sciences Center, which will
allow the Company to monetize approximately $276 of state research
and development tax credits. In exchange for these incentives, the
Company pledged to hire an incremental fifteen employees and to
maintain the additional headcount through at least
December 31, 2018. Failure to do so could result in the
Company being required to repay some or all of these incentives. As
the Company met the additional headcount during the quarter ended
June 30, 2014, the Company has deferred and is amortizing the
benefit of this monetization on a straight-line basis over the
five-year performance period.</p>
</div>
<div>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt">
<b><i>Contingent consideration</i></b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%">
Each reporting period, the Company revalues the contingent
consideration obligations associated with business combinations to
their fair value and record within operating expenses increases in
their fair value as contingent consideration expense and decreases
in the fair value as contingent consideration income. Changes in
contingent consideration result from changes in the assumptions
regarding probabilities of successful achievement of related
milestones, the estimated timing in which the milestones are
achieved and the discount rate used to estimate the fair value of
the liability. Contingent consideration may change significantly as
development of the Company’s clinical programs in certain
indications progress and additional data are obtained, impacting
the Company’s assumptions. The assumptions used in estimating
fair value require significant judgment. The use of different
assumptions and judgments could result in a materially different
estimate of fair value. See Note 3, “Fair value
measurements,” for additional information.</p>
</div>
<div>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%">
The acquisition-date fair value of the purchase consideration is as
follows:</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 12pt; MARGIN-TOP: 0pt">
 </p>
<table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="68%" align="center" border="0">
<tr>
<td width="88%"></td>
<td valign="bottom" width="6%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Cash</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">5,093</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Common stock</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">19,348</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Contingent consideration</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">6,550</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Total purchase consideration</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">30,991</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
</div>
1490000
0
75000
0
15
3000
151000
0.30
2026
0.15
2019-03-19
2015
0.10
0.50
12500000
2
P2Y
P3Y
P3Y
6550000
94000
27000
4112000
338000
0.155
405000
2014-06-30
P8Y
30991000
5093000
82000
P1Y
P18M
P18M
2000
94000
31000
4812000
2000
0.95
42000
42000
P5Y
P4Y
960000
450000
3450000
7524000
109776000
306000
276000
2151000
-2.13
4440000
6334000
-4583000
6249000
-4583000
-389000
-4194000
-4583000
85000
10528000
3281000
1657000
7247000
110000
3890000
440000
34000
1623000
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4571000
6335000
-1526000
6250000
-13323000
11000
-13334000
-1526000
85000
19669000
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13931000
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