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<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="5" face="Times New Roman" style="font-size:18.0pt;font-weight:bold;">UNITED STATES<br> SECURITIES AND EXCHANGE COMMISSION</font></b></p>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Washington, D.C. 20549</font></b></p>
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<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="5" face="Times New Roman" style="font-size:18.0pt;font-weight:bold;">FORM&nbsp;8-K</font></b></p>
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<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="3" face="Times New Roman" style="font-size:12.0pt;font-weight:bold;">CURRENT REPORT</font></b></p>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="3" face="Times New Roman" style="font-size:12.0pt;font-weight:bold;">Pursuant to Section&nbsp;13 or 15(d)&nbsp;of the Securities Exchange Act of 1934</font></b></p>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Date of Report (Date of earliest event reported):&#160; <b>April&nbsp;29, 2013</b></font></p>
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<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="5" face="Times New Roman" style="font-size:18.0pt;font-weight:bold;">INSMED INCORPORATED</font></b></p>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(Exact name of registrant as specified in its charter)</font></p>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">&nbsp;</font></b></p>
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<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Virginia</font></b></p>    </td>
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<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">0-30739</font></b></p>    </td>
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<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:1.0pt;font-weight:bold;">&nbsp;</font></b></p>    </td>
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<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">54-1972729</font></b></p>    </td>   </tr>
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<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(State or other jurisdiction of Incorporation)</font></p>    </td>
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<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
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<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(Commission File Number)</font></p>    </td>
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<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
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<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(I.R.S. Employer Identification No.)</font></p>    </td>   </tr>  </table>
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<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">9 Deer Park Drive, Suite&nbsp;C,</font></b></p>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Monmouth Junction, New Jersey</font></b></p>    </td>
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<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:1.0pt;font-weight:bold;">&nbsp;</font></b></p>    </td>
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<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">08852</font></b></p>    </td>   </tr>
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<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(Address of principal executive offices)</font></p>    </td>
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<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(Zip Code)</font></p>    </td>   </tr>  </table>
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<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Registrant&#146;s telephone number, including area code: (<b>732) 997-4600</b></font></p>
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<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Not Applicable</font></b></p>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(Former name or former address, if changed from last report.)</font></p>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Check the appropriate box below if the Form&nbsp;8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:</font></p>
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<p style="margin:0in 0in .0001pt .25in;text-indent:-.25in;"><font size="2" face="Wingdings" style="font-size:10.0pt;">o</font><font size="1" style="font-size:3.0pt;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font><font size="2" style="font-size:10.0pt;">Written communications pursuant to Rule&nbsp;425 under the Securities Act (17 CFR 230.425)</font></p>
<p style="margin:0in 0in .0001pt .25in;text-indent:-.25in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<p style="margin:0in 0in .0001pt .25in;text-indent:-.25in;"><font size="2" face="Wingdings" style="font-size:10.0pt;">o</font><font size="1" style="font-size:3.0pt;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font><font size="2" style="font-size:10.0pt;">Soliciting material pursuant to Rule&nbsp;14a-12 under the Exchange Act (17 CFR 240.14a-12)</font></p>
<p style="margin:0in 0in .0001pt .25in;text-indent:-.25in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<p style="margin:0in 0in .0001pt .25in;text-indent:-.25in;"><font size="2" face="Wingdings" style="font-size:10.0pt;">o</font><font size="1" style="font-size:3.0pt;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font><font size="2" style="font-size:10.0pt;">Pre-commencement communications pursuant to Rule&nbsp;14d-2(b)&nbsp;under the Exchange Act (17 CFR 240.14d-2(b))</font></p>
<p style="margin:0in 0in .0001pt .25in;text-indent:-.25in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<p style="margin:0in 0in .0001pt .25in;text-indent:-.25in;"><font size="2" face="Wingdings" style="font-size:10.0pt;">o</font><font size="1" style="font-size:3.0pt;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font><font size="2" style="font-size:10.0pt;">Pre-commencement communications pursuant to Rule&nbsp;13e-4(c)&nbsp;under the Exchange Act (17 CFR 240.13e-4(c))</font></p>
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<p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Item&nbsp;8.01 &#151; Other Events.</font></b></p>
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">As previously disclosed by Insmed Incorporated (the &#147;Company&#148;) in its Annual Report on Form&nbsp;10-K for the year ended December&nbsp;31, 2012 (the &#147;Annual Report), the Company entered into an agreement with Premacure AB, now Shire plc, (&#147;Premacure&#148;) in May&nbsp;2012 pursuant to which the Company granted Premacure an exclusive, worldwide license to develop, manufacture and commercialize IGF-1, with its natural binding protein,&nbsp;IGFBP-3, for the prevention and treatment of complications of preterm birth (the &#147;Premacure License Agreement&#148;).&#160; As further disclosed in the Annual Report, in March&nbsp;2013, the Company amended the Premacure License Agreement to provide Premacure with an option to obtain all of the Company&#146;s right to receive revenues from the commercialization of IGF-1 under the Premacure License Agreement in exchange for a cash payment to the Company of $11.5 million (the &#147;Buyout Amount&#148;).</font></p>
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Premacure exercised this option on April&nbsp;29, 2013.&#160; Premacure is obligated to pay the Buyout Amount to the Company in full within ten days after the date of exercise.&#160; As a result of option exercise, the Company will not be entitled to any future royalties from Premacure, and Premacure will assume the Company&#146;s royalty obligations to other parties.</font></p>
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<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">2<a name="PB_2_171628_7056"></a></font></p>
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<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">SIGNATURE</font></b></p>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.</font></p>
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">April&nbsp;30, 2013</font></p>
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
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<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">INSMED INCORPORATED</font></p>    </td>   </tr>
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<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
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<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
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<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">By:</font></p>    </td>
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<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">/s/   Andrew T. Drechsler</font></p>    </td>   </tr>
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<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Name:</font></p>    </td>
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<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Andrew   T. Drechsler</font></p>    </td>   </tr>
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<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
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<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Title:</font></p>    </td>
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<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Chief   Financial Officer</font></p>    </td>   </tr>  </table>
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<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">3<a name="PB_3_171649_5335"></a></font></p>
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{"company-data": {"conformed-name": "INSMED INC", "cik": "0001104506", "assigned-sic": "2834", "irs-number": "541972729", "state-of-incorporation": "VA", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "8-K", "act": "34", "file-number": "000-30739", "film-number": "13794428"}, "business-address": {"street1": "9 DEER PARK DRIVE", "street2": "SUITE C", "city": "MONMOUTH JUNCTION", "state": "NJ", "zip": "08852", "phone": "732-997-4600"}, "mail-address": {"street1": "9 DEER PARK DRIVE", "street2": "SUITE C", "city": "MONMOUTH JUNCTION", "state": "NJ", "zip": "08852"}}
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM 8-K
CURRENT REPORT
Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934
Date of Report (Date of earliest event reported):
April 29, 2013
INSMED INCORPORATED
(Exact name of registrant as specified in its charter)
Virginia
0-30739
54-1972729
(State or other jurisdiction of Incorporation)
(Commission File Number)
(I.R.S. Employer Identification No.)
9 Deer Park Drive, Suite C,
Monmouth Junction, New Jersey
08852
(Address of principal executive offices)
(Zip Code)
Registrant's telephone number, including area code: (
732) 997-4600
Not Applicable
(Former name or former address, if changed from last report.)
Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:
o
Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)
o
Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)
o
Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))
o
Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))
Item 8.01 — Other Events.
As previously disclosed by Insmed Incorporated (the "Company") in its Annual Report on Form 10-K for the year ended December 31, 2012 (the "Annual Report), the Company entered into an agreement with Premacure AB, now Shire plc, ("Premacure") in May 2012 pursuant to which the Company granted Premacure an exclusive, worldwide license to develop, manufacture and commercialize IGF-1, with its natural binding protein, IGFBP-3, for the prevention and treatment of complications of preterm birth (the "Premacure License Agreement").  As further disclosed in the Annual Report, in March 2013, the Company amended the Premacure License Agreement to provide Premacure with an option to obtain all of the Company's right to receive revenues from the commercialization of IGF-1 under the Premacure License Agreement in exchange for a cash payment to the Company of $11.5 million (the "Buyout Amount").
Premacure exercised this option on April 29, 2013.  Premacure is obligated to pay the Buyout Amount to the Company in full within ten days after the date of exercise.  As a result of option exercise, the Company will not be entitled to any future royalties from Premacure, and Premacure will assume the Company's royalty obligations to other parties.
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SIGNATURE
Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.
April 30, 2013
INSMED INCORPORATED
By:
/s/   Andrew T. Drechsler
Name:
Andrew   T. Drechsler
Title:
Chief   Financial Officer
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