SEC Contract Filing

Filing Date: 2016-02-25

Document Content:
<DOCUMENT>
<TYPE>EX-10.21
<SEQUENCE>2
<FILENAME>xlrn-20151231xex1021.htm
<DESCRIPTION>EXHIBIT 10.21
<TEXT>
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<a name="s0876D1621B1256FB70E3F192138E0A00"></a><div><div style="line-height:120%;text-align:right;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">Exhibit 10.21</font></div></div><br><div style="line-height:120%;text-align:center;font-size:10pt;"><div style="padding-left:0px;text-indent:0px;line-height:normal;padding-top:10px;"><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman;font-size:10pt;margin-left:auto;margin-right:auto;width:100%;border-collapse:collapse;text-align:left;"><tr><td colspan="2"></td></tr><tr><td width="65%"></td><td width="35%"></td></tr><tr><td style="vertical-align:top;border-bottom:1px solid #00000a;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;border-left:1px solid #00000a;border-right:1px solid #00000a;border-top:1px solid #00000a;"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">Name:</font></div></td><td style="vertical-align:top;border-bottom:1px solid #00000a;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;border-left:1px solid #00000a;border-right:1px solid #00000a;border-top:1px solid #00000a;"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">[&#9679;]</font></div></td></tr><tr><td style="vertical-align:top;border-bottom:1px solid #00000a;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;border-left:1px solid #00000a;border-right:1px solid #00000a;border-top:1px solid #00000a;"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">Number of Restricted Stock Units subject to Award:</font></div></td><td style="vertical-align:top;border-bottom:1px solid #00000a;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;border-left:1px solid #00000a;border-right:1px solid #00000a;border-top:1px solid #00000a;"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">[&#9679;]</font></div></td></tr><tr><td style="vertical-align:top;border-bottom:1px solid #00000a;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;border-left:1px solid #00000a;border-right:1px solid #00000a;border-top:1px solid #00000a;"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">Date of Grant:</font></div></td><td style="vertical-align:top;border-bottom:1px solid #00000a;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;border-left:1px solid #00000a;border-right:1px solid #00000a;border-top:1px solid #00000a;"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">[&#9679;]</font></div></td></tr></table></div></div><div style="line-height:120%;padding-bottom:16px;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:120%;padding-bottom:16px;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">ACCELERON PHARMA INC.</font></div><div style="line-height:120%;padding-bottom:16px;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">2013 EQUITY INCENTIVE PLAN</font></div><div style="line-height:120%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;text-decoration:underline;">RESTRICTED STOCK UNIT AWARD AGREEMENT</font></div><div style="line-height:120%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:120%;text-align:justify;text-indent:48px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">This agreement (the &#8220;</font><font style="font-family:inherit;font-size:10pt;text-decoration:underline;">Agreement</font><font style="font-family:inherit;font-size:10pt;">&#8221;) evidences an award (the &#8220;</font><font style="font-family:inherit;font-size:10pt;text-decoration:underline;">Award</font><font style="font-family:inherit;font-size:10pt;">&#8221;) of restricted stock units (the &#8220;</font><font style="font-family:inherit;font-size:10pt;text-decoration:underline;">Restricted Stock Units</font><font style="font-family:inherit;font-size:10pt;">&#8221;) granted by Acceleron Pharma Inc. (the &#8220;</font><font style="font-family:inherit;font-size:10pt;text-decoration:underline;">Company</font><font style="font-family:inherit;font-size:10pt;">&#8221;) to the undersigned</font><font style="font-family:inherit;font-size:10pt;font-weight:bold;">&#32;</font><font style="font-family:inherit;font-size:10pt;">(the &#8220;</font><font style="font-family:inherit;font-size:10pt;text-decoration:underline;">Participant</font><font style="font-family:inherit;font-size:10pt;">&#8221;) pursuant and subject to the terms and conditions of the Acceleron Pharma Inc. 2013 Equity Incentive Plan (as amended from time to time, the &#8220;</font><font style="font-family:inherit;font-size:10pt;text-decoration:underline;">Plan</font><font style="font-family:inherit;font-size:10pt;">&#8221;),</font><font style="font-family:inherit;font-size:10pt;font-weight:bold;">&#32;</font><font style="font-family:inherit;font-size:10pt;">which is incorporated herein by reference. Except as otherwise defined herein, all capitalized terms used herein have the same meaning as in the Plan.</font></div><div style="line-height:120%;text-