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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;">As filed with the Securities and Exchange Commission on April&nbsp;30, 2013</font></b></p>
<p align="right" style="margin:0in 0in .0001pt;text-align:right;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Registration No.&nbsp;333-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</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;">UNITED STATES</font></b></p>
<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;">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.&#160; 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;S-8</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;">REGISTRATION STATEMENT</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;">UNDER</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;">THE SECURITIES ACT OF 1933</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;">United Therapeutics Corporation</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 the Charter)</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;">Delaware</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;">52-1984749</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<br>   or organization)</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 style="margin:0in 0in .0001pt;"><font size="1" face="Times New Roman" style="font-size:9.0pt;">&nbsp;</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;">1040 Spring Street<br>   Silver Spring, MD</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;">20910</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 align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="1" face="Times New Roman" style="font-size:9.0pt;">&nbsp;</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;">UNITED THERAPEUTICS CORPORATION <br> 2011 SHARE TRACKING AWARDS PLAN</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;">(Full title of the plan)</font></p>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="1" face="Times New Roman" style="font-size:9.0pt;">&nbsp;</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;">Martine A. Rothblatt, Chairman and Chief Executive Officer</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;">United Therapeutics Corporation</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;">1040 Spring Street</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;">Silver Spring, MD 20910<br> (301) 608-9292<br>  </font></b><font size="2" style="font-size:10.0pt;">(Name, address and telephone number, including area code, of agent for service)</font></p>
<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="1" face="Times New Roman" style="font-size:9.0pt;">&nbsp;</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;">Copy to:</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;">Stephen I. Glover,&nbsp;Esq.</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;">John S. Hess,&nbsp;Jr.,&nbsp;Esq.</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;">Gibson, Dunn&nbsp;&amp; Crutcher LLP</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;">Vice President and Associate General   Counsel</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:10.0pt;">1050 Connecticut Avenue, N.W.</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;">United Therapeutics Corporation</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:10.0pt;">Washington, D.C. 20036</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;">1735 Connecticut Avenue, N.W.</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:10.0pt;">(202) 955-8500</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;">Washington, D.C. 20009</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 align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(202) 483-7000</font></p>    </td>   </tr>  </table>
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<p style="margin:0in 0in .0001pt;"><font size="1" face="Times New Roman" style="font-size:9.0pt;">&nbsp;</font></p>
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company.&#160; See the definitions of &#147;large accelerated filer,&#148; &#147;accelerated filer&#148; and &#147;smaller reporting company&#148; in Rule&nbsp;12b-2 of the Exchange Act.</font></p>
<p style="margin:0in 0in .0001pt;"><font size="1" face="Times New Roman" style="font-size:9.0pt;">&nbsp;</font></p>
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<p style="margin:0in 0in .0001pt 46.1pt;text-indent:-10.1pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Large accelerated filer </font><font size="2" face="Wingdings" style="font-size:10.0pt;">x</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 style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Accelerated filer </font><font size="2" face="Wingdings" style="font-size:10.0pt;">o</font></p>    </td>   </tr>
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<p style="margin:0in 0in .0001pt 10.0pt;text-indent:-10.0pt;"><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>
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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 46.1pt;text-indent:-10.1pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Non-accelerated filer </font><font size="2" face="Wingdings" style="font-size:10.0pt;">o</font><font size="2" style="font-size:10.0pt;"> (Do not check if a   smaller reporting company)</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 style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Smaller reporting company </font><font size="2" face="Wingdings" style="font-size:10.0pt;">o</font></p>    </td>   </tr>  </table>
<p style="margin:0in 0in .0001pt;"><font size="1" face="Times New Roman" style="font-size:9.0pt;">&nbsp;</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;">CALCULATION OF REGISTRATION FEE</font></b></p>
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<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="1" face="Times New Roman" style="font-size:8.0pt;font-weight:bold;">Title&nbsp;of<br>   Securities&nbsp;to&nbsp;be<br>   Registered</font></b></p>    </td>
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<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="1" 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="1" face="Times New Roman" style="font-size:8.0pt;font-weight:bold;">Amount&nbsp;to&nbsp;be<br>   Registered</font></b></p>    </td>
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<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="1" 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="1" face="Times New Roman" style="font-size:8.0pt;font-weight:bold;">Proposed&nbsp;Maximum<br>   Offering&nbsp;Price&nbsp;Per&nbsp;Share&nbsp;(3)</font></b></p>    </td>
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<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="1" 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="1" face="Times New Roman" style="font-size:8.0pt;font-weight:bold;">Proposed&nbsp;Maximum<br>   Aggregate&nbsp;Offering<br>   Price&nbsp;(3)</font></b></p>    </td>
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<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="1" 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="1" face="Times New Roman" style="font-size:8.0pt;font-weight:bold;">Amount&nbsp;of<br>   Registration<br>   Fee</font></b></p>    </td>
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<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="1" face="Times New Roman" style="font-size:1.0pt;font-weight:bold;">&nbsp;</font></b></p>    </td>   </tr>
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<p style="margin:0in 0in .0001pt 10.0pt;text-indent:-10.0pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Share Tracking Awards (1)&nbsp;(2)</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="right" style="margin:0in 0in .0001pt;text-align:right;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">3,200,000 awards</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>
<td width="1%" valign="bottom" bgcolor="black" style="background:white;border:none;border-bottom:double windowtext 2.25pt;padding:0in 0in 0in 0in;width:1.3%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">$</font></p>    </td>
<td width="16%" valign="bottom" bgcolor="black" style="background:white;border:none;border-bottom:double windowtext 2.25pt;padding:0in 0in 0in 0in;width:16.7%;">
<p align="right" style="margin:0in 0in .0001pt;text-align:right;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">60.455</font></p>    </td>
<td width="2%" valign="bottom" bgcolor="black" style="background:white;border:none;border-bottom:double windowtext 2.25pt;padding:0in 0in 0in 0in;width:2.5%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="1%" valign="bottom" bgcolor="black" style="background:white;border:none;border-bottom:double windowtext 2.25pt;padding:0in 0in 0in 0in;width:1.3%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">$</font></p>    </td>
<td width="13%" valign="bottom" bgcolor="black" style="background:white;border:none;border-bottom:double windowtext 2.25pt;padding:0in 0in 0in 0in;width:13.7%;">
<p align="right" style="margin:0in 0in .0001pt;text-align:right;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">193,456,000</font></p>    </td>
<td width="2%" valign="bottom" bgcolor="black" style="background:white;border:none;border-bottom:double windowtext 2.25pt;padding:0in 0in 0in 0in;width:2.5%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="1%" valign="bottom" bgcolor="black" style="background:white;border:none;border-bottom:double windowtext 2.25pt;padding:0in 0in 0in 0in;width:1.3%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">$</font></p>    </td>
<td width="10%" valign="bottom" bgcolor="black" style="background:white;border:none;border-bottom:double windowtext 2.25pt;padding:0in 0in 0in 0in;width:10.7%;">
<p align="right" style="margin:0in 0in .0001pt;text-align:right;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">26,387.40</font></p>    </td>
<td width="1%" valign="bottom" bgcolor="black" style="background:white;border:none;border-bottom:double windowtext 2.25pt;padding:0in 0in 0in 0in;width:1.0%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>   </tr>
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<p style="margin:0in 0in .0001pt .25in;text-indent:-.25in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(1)</font><font size="1" style="font-size:3.0pt;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font><font size="2" style="font-size:10.0pt;">This Registration Statement relates to share tracking awards that may be issued under the United Therapeutics Corporation 2011 Share Tracking Awards Plan.</font></p>
<p style="margin:0in 0in .0001pt;"><font size="1" face="Times New Roman" style="font-size:9.0pt;">&nbsp;</font></p>
<p style="margin:0in 0in .0001pt .25in;text-indent:-.25in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(2)</font><font size="1" style="font-size:3.0pt;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font><font size="2" style="font-size:10.0pt;">Pursuant to Rule&nbsp;416 under the Securities Act of 1933 (the &#147;Securities Act&#148;), this Registration Statement shall also cover any additional securities in respect of the securities identified in the above table as a result of any stock dividend, stock split, recapitalization or other similar transactions.</font></p>
<p style="margin:0in 0in .0001pt .25in;text-indent:-.25in;"><font size="1" face="Times New Roman" style="font-size:9.0pt;">&nbsp;</font></p>
<p style="margin:0in 0in .0001pt .25in;text-indent:-.25in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(3)</font><font size="1" style="font-size:3.0pt;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font><font size="2" style="font-size:10.0pt;">Estimated solely for the purpose of calculating the amount of the registration fee pursuant to Rule&nbsp;457(h)(1)&nbsp;under the Securities Act. The price per share and aggregate offering price are based upon the average of the high and low prices of the Registrant&#146;s common stock as reported on the NASDAQ Global Select Market for April&nbsp;25, 2013.</font></p>
<p style="margin:0in 0in .0001pt;"><font size="1" face="Times New Roman" style="font-size:9.0pt;">&nbsp;</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;">INTRODUCTION</font></b></p>
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<p style="margin:0in 0in .0001pt;text-indent:.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">This Registration Statement on Form&nbsp;S-8 is filed by United Therapeutics Corporation, a Delaware corporation (the &#147;Company&#148; or the &#147;Registrant&#148;), to register an additional 3,200,000 share tracking awards (the &#147;Awards&#148;), which have been and will be granted in accordance with the terms of the United Therapeutics 2011 Share Tracking Awards Plan (the &#147;Plan&#148;).&#160; Each award represents a contractual right to receive an amount in cash equal to the positive difference, if any, between the fair market value of the Award on the exercise date and the fair market value of the Award on the grant date.&#160; The fair market value of an Award on the grant date or the exercise date is equal to the closing price per share of the Company&#146;s common stock on that date.</font></p>
<p style="margin:0in 0in .0001pt;text-indent:.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<p style="margin:0in 0in .0001pt;text-indent:.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">The Company previously filed with the Securities and Exchange Commission (the &#147;Commission&#148;): (a)&nbsp;a registration statement on Form&nbsp;S-8 (File No.&nbsp;333-173858) on May&nbsp;2, 2011 registering 2,000,000 Awards under the Plan and (b)&nbsp;a registration statement on Form&nbsp;S-8 (File No.&nbsp;333-179746) on February&nbsp;28, 2012 registering an additional 2,000,000 Awards under the Plan (together, the &#147;Prior Registration Statements&#148;).&#160; On October&nbsp;30, 2012 and February&nbsp;1, 2013, a majority of the Company&#146;s Board of Directors, in each case acting upon the recommendation of its Compensation Committee, approved amendments to the Plan to increase the maximum number of Awards available for grant under the Plan by 1,800,000 and 1,400,000 Awards, respectively (the &#147;Second Amendment&#148; and &#147;Third Amendment,&#148; respectively), raising the total number of Awards available for grant under the Plan to 7,200,000 Awards.&#160; The Second Amendment is described in the Company&#146;s Quarterly Report on Form&nbsp;10-Q, filed with the Commission on November&nbsp;1, 2012, and is filed as Exhibit&nbsp;10.1 thereto.&#160; The Third Amendment is described in the Company&#146;s Current Report on Form&nbsp;8-K, filed with the Commission on February&nbsp;4, 2013, and is filed as Exhibit&nbsp;10.1 thereto.&#160; The Plan was originally filed with the Commission on March&nbsp;18, 2011 as Exhibit&nbsp;10.1 to the Company&#146;s Current Report on Form&nbsp;8-K.</font></p>
<p style="margin:0in 0in .0001pt;text-indent:.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<p style="margin:0in 0in .0001pt;text-indent:.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">In accordance with General Instruction E of Form&nbsp;S-8, the entire contents of the Prior Registration Statements are incorporated herein by reference, and certain information required by Part&nbsp;II is omitted.</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;">PART&nbsp;I</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;">INFORMATION REQUIRED IN THE SECTION&nbsp;10(a)&nbsp;PROSPECTUS</font></b></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 1.</font></b><b><font size="1" style="font-size:3.0pt;font-weight:bold;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font></b><b><font size="2" style="font-size:10.0pt;font-weight:bold;">Plan Information</font></b><font size="2" style="font-size:10.0pt;">*</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;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Item 2.</font></b><b><font size="1" style="font-size:3.0pt;font-weight:bold;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font></b><b><font size="2" style="font-size:10.0pt;font-weight:bold;">Registrant Information and Employee Plan Annual Information</font></b><font size="2" style="font-size:10.0pt;">*</font></p>
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<div style="margin:0in 0in .0001pt;"><hr size="1" width="25%" noshade color="black" align="left"></div>
<p style="margin:0in 0in .0001pt .5in;text-indent:-21.0pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">*</font><font size="1" style="font-size:3.0pt;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font><font size="2" style="font-size:10.0pt;">Information required by Part&nbsp;I to be contained in the Section&nbsp;10(a)&nbsp;prospectus is omitted from this Registration Statement in accordance with Rule&nbsp;428 under the Securities Act and the Note to Part&nbsp;I of Form&nbsp;S-8.</font></p>
<p style="margin:0in 0in .0001pt .5in;text-indent:-.5in;"><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;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">PART&nbsp;II</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;">INFORMATION REQUIRED IN THE REGISTRATION STATEMENT</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;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Item 3.</font></b><b><font size="1" style="font-size:3.0pt;font-weight:bold;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font></b><b><font size="2" style="font-size:10.0pt;font-weight:bold;">Incorporation of Documents by Reference</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;text-indent:.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">The following documents, which have heretofore been filed by the Company with the Commission</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;">1<a name="PB_1_200028_7056"></a></font></p>
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<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">pursuant to the Securities Act, and pursuant to the Securities Exchange Act of 1934, as amended (the &#147;Exchange Act&#148;), are incorporated by reference herein and shall be deemed to be a part hereof:</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 .5in;text-indent:-.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(1)</font><font size="1" style="font-size:3.0pt;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font><font size="2" style="font-size:10.0pt;">The Annual Report on Form&nbsp;10-K for the fiscal year ended December&nbsp;31, 2012, which the Company filed with the Commission on February&nbsp;26, 2013; and</font></p>
<p style="margin:0in 0in .0001pt .5in;text-indent:-.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<p style="margin:0in 0in .0001pt .5in;text-indent:-.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(2)</font><font size="1" style="font-size:3.0pt;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font><font size="2" style="font-size:10.0pt;">All other reports filed pursuant to Section&nbsp;13(a)&nbsp;or 15(d)&nbsp;of the Exchange Act since the end of the fiscal year covered by the Company&#146;s Annual Report referred to in (1)&nbsp;above.</font></p>
<p style="margin:0in 0in .0001pt .5in;text-indent:-.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<p style="margin:0in 0in .0001pt;text-indent:.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">In addition, all documents filed by the Company or the Plan pursuant to Sections 13(a), 13(c), 14 or 15(d)&nbsp;of the Exchange Act prior to the filing of a post-effective amendment to this Registration Statement which indicates that all securities offered hereby have been sold or which deregisters all such securities then remaining unsold, shall be deemed to be incorporated by reference in this Registration Statement and made a part hereof from their respective dates of filing (such documents, and the documents listed above, being hereinafter referred to as &#147;Incorporated Documents&#148;); provided, however, that the documents listed above or subsequently filed by the Company or the Plan pursuant to Sections 13(a), 13(c), 14 and 15(d)&nbsp;of the Exchange Act in each year during which the offering made by this Registration Statement is in effect prior to the filing with the Commission of the Company&#146;s Annual Report on Form&nbsp;10-K covering such year shall cease to be Incorporated Documents or to be incorporated by reference in this Registration Statement from and after the filing of such Annual Reports.</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;text-indent:.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Any statement contained herein shall be deemed to be modified or superseded for purposes of this Registration Statement to the extent that a statement contained in any subsequently filed Incorporated Document modifies or supersedes such statement.&#160; Any statement contained in an Incorporated Document shall be deemed to be modified or superseded for purposes of this Registration Statement to the extent that a statement contained herein or in any other subsequently filed Incorporated Document modifies or supersedes such statement.&#160; Any such statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this Registration Statement.</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;text-indent:.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">The Company&#146;s Exchange Act file number with the Commission is 000-26301.</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;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Item 8.</font></b><b><font size="1" style="font-size:3.0pt;font-weight:bold;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font></b><b><font size="2" style="font-size:10.0pt;font-weight:bold;">Exhibits</font></b></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;punctuation-wrap:simple;"><b><font size="1" face="Times New Roman" style="font-size:8.0pt;font-weight:bold;">Exhibit&nbsp;No.</font></b></p>    </td>
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<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><b><font size="1" face="Times New Roman" style="font-size:8.0pt;font-weight:bold;">Description</font></b></p>    </td>   </tr>
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<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">4.1</font></p>    </td>
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<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Amended and Restated Certificate of Incorporation of the Company   (incorporated by reference to Exhibit&nbsp;3.1 of the Company&#146;s Registration   Statement on Form&nbsp;S-1 (Registration No.&nbsp;333-76409))</font></p>    </td>   </tr>
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<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.22%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="10%" valign="top" style="padding:0in 0in 0in 0in;width:10.34%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">4.2</font></p>    </td>
<td width="3%" valign="bottom" style="padding:0in 0in 0in 0in;width:3.44%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.22%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Certificate of Amendment to Amended and Restated Certificate of   Incorporation of the Company (incorporated by reference to Exhibit&nbsp;3.1   of the Company&#146;s Current Report on Form&nbsp;8-K, filed on June&nbsp;28,   2010)</font></p>    </td>   </tr>
<tr>
<td width="10%" valign="top" style="padding:0in 0in 0in 0in;width:10.34%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="3%" valign="bottom" style="padding:0in 0in 0in 0in;width:3.44%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.22%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="10%" valign="top" style="padding:0in 0in 0in 0in;width:10.34%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">4.3</font></p>    </td>
<td width="3%" valign="bottom" style="padding:0in 0in 0in 0in;width:3.44%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.22%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Second Amended and Restated Bylaws of the Company, as amended   (incorporated by reference to Exhibit&nbsp;3.2 of the Company&#146;s Quarterly   Report on Form&nbsp;10-Q for the quarter ended March&nbsp;31, 2008)</font></p>    </td>   </tr>
<tr>
<td width="10%" valign="top" style="padding:0in 0in 0in 0in;width:10.34%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="3%" valign="bottom" style="padding:0in 0in 0in 0in;width:3.44%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.22%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="10%" valign="top" style="padding:0in 0in 0in 0in;width:10.34%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">5.1</font></p>    </td>
<td width="3%" valign="bottom" style="padding:0in 0in 0in 0in;width:3.44%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.22%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Opinion of counsel*</font></p>    </td>   </tr>  </table>
<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;">2<a name="PB_2_200028_5335"></a></font></p>
<div style="margin:0in 0in .0001pt;"><hr size="3" width="100%" noshade color="#010101" align="left"></div>
</div>
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<div>
<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>
<table border="0" cellspacing="0" cellpadding="0" width="96%" style="border-collapse:collapse;margin-left:.25in;width:96.66%;">
<tr>
<td width="10%" valign="top" style="padding:0in 0in 0in 0in;width:10.34%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">10.1</font></p>    </td>
<td width="3%" valign="bottom" style="padding:0in 0in 0in 0in;width:3.44%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.22%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">United Therapeutics Corporation 2011 Share Tracking Awards Plan   (incorporated by reference to Exhibit&nbsp;10.1 of the Company&#146;s Current   Report on Form&nbsp;8-K, filed on March&nbsp;18, 2011)</font></p>    </td>   </tr>
<tr>
<td width="10%" valign="top" style="padding:0in 0in 0in 0in;width:10.34%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="3%" valign="bottom" style="padding:0in 0in 0in 0in;width:3.44%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.22%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="10%" valign="top" style="padding:0in 0in 0in 0in;width:10.34%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">10.2</font></p>    </td>
<td width="3%" valign="bottom" style="padding:0in 0in 0in 0in;width:3.44%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.22%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">First Amendment to the United Therapeutics Corporation 2011 Share   Tracking Awards Plan, effective as of February&nbsp;1, 2012 (incorporated by   reference to Exhibit&nbsp;10.2 of the Company&#146;s Current Report on   Form&nbsp;8-K, filed on February&nbsp;6, 2012)</font></p>    </td>   </tr>
<tr>
<td width="10%" valign="top" style="padding:0in 0in 0in 0in;width:10.34%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="3%" valign="bottom" style="padding:0in 0in 0in 0in;width:3.44%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.22%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="10%" valign="top" style="padding:0in 0in 0in 0in;width:10.34%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">10.3</font></p>    </td>
<td width="3%" valign="bottom" style="padding:0in 0in 0in 0in;width:3.44%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.22%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Second Amendment to the United Therapeutics Corporation 2011 Share   Tracking Awards Plan, effective as of October&nbsp;30, 2012 (incorporated by   reference to Exhibit&nbsp;10.1 of the Company&#146;s Quarterly Report on   Form&nbsp;10-Q for the quarter ended September&nbsp;30, 2012)</font></p>    </td>   </tr>
<tr>
<td width="10%" valign="top" style="padding:0in 0in 0in 0in;width:10.34%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="3%" valign="bottom" style="padding:0in 0in 0in 0in;width:3.44%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.22%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="10%" valign="top" style="padding:0in 0in 0in 0in;width:10.34%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">10.4</font></p>    </td>
<td width="3%" valign="bottom" style="padding:0in 0in 0in 0in;width:3.44%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.22%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Third Amendment to the United Therapeutics Corporation 2011 Share   Tracking Awards Plan, effective as of February&nbsp;1, 2013 (incorporated by   reference to Exhibit&nbsp;10.1 of the Company&#146;s Current Report on   Form&nbsp;8-K, filed on February&nbsp;4, 2013)</font></p>    </td>   </tr>
<tr>
<td width="10%" valign="top" style="padding:0in 0in 0in 0in;width:10.34%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="3%" valign="bottom" style="padding:0in 0in 0in 0in;width:3.44%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.22%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="10%" valign="top" style="padding:0in 0in 0in 0in;width:10.34%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">10.5</font></p>    </td>
<td width="3%" valign="bottom" style="padding:0in 0in 0in 0in;width:3.44%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.22%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Form&nbsp;of Terms and Conditions for Awards to Employees   (incorporated by reference to Exhibit&nbsp;10.2 of the Company&#146;s Registration   Statement on Form&nbsp;S-8, filed on May&nbsp;2, 2011 (Registration   No.&nbsp;333-173858))</font></p>    </td>   </tr>
<tr>
<td width="10%" valign="top" style="padding:0in 0in 0in 0in;width:10.34%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="3%" valign="bottom" style="padding:0in 0in 0in 0in;width:3.44%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.22%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="10%" valign="top" style="padding:0in 0in 0in 0in;width:10.34%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">10.6</font></p>    </td>
<td width="3%" valign="bottom" style="padding:0in 0in 0in 0in;width:3.44%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.22%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Form&nbsp;of Terms and Conditions for Awards to Non-Employees   (incorporated by reference to Exhibit&nbsp;10.3 of the Company&#146;s Current   Report on Form&nbsp;8-K, filed on March&nbsp;18, 2011)</font></p>    </td>   </tr>
<tr>
<td width="10%" valign="top" style="padding:0in 0in 0in 0in;width:10.34%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="3%" valign="bottom" style="padding:0in 0in 0in 0in;width:3.44%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.22%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="10%" valign="top" style="padding:0in 0in 0in 0in;width:10.34%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">10.7</font></p>    </td>
<td width="3%" valign="bottom" style="padding:0in 0in 0in 0in;width:3.44%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.22%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Form&nbsp;of Grant Letter used by Registrant (incorporated by   reference to Exhibit&nbsp;10.4 of the Company&#146;s Current Report on   Form&nbsp;8-K, filed on March&nbsp;18, 2011)</font></p>    </td>   </tr>
<tr>
<td width="10%" valign="top" style="padding:0in 0in 0in 0in;width:10.34%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="3%" valign="bottom" style="padding:0in 0in 0in 0in;width:3.44%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.22%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="10%" valign="top" style="padding:0in 0in 0in 0in;width:10.34%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">23.1</font></p>    </td>
<td width="3%" valign="bottom" style="padding:0in 0in 0in 0in;width:3.44%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.22%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Consent of Independent Registered Public Accounting Firm*</font></p>    </td>   </tr>
<tr>
<td width="10%" valign="top" style="padding:0in 0in 0in 0in;width:10.34%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="3%" valign="bottom" style="padding:0in 0in 0in 0in;width:3.44%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.22%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="10%" valign="top" style="padding:0in 0in 0in 0in;width:10.34%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">23.2</font></p>    </td>
<td width="3%" valign="bottom" style="padding:0in 0in 0in 0in;width:3.44%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.22%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Consent of counsel (included in Exhibit&nbsp;5.1)*</font></p>    </td>   </tr>
<tr>
<td width="10%" valign="top" style="padding:0in 0in 0in 0in;width:10.34%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="3%" valign="bottom" style="padding:0in 0in 0in 0in;width:3.44%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.22%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="10%" valign="top" style="padding:0in 0in 0in 0in;width:10.34%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">24</font></p>    </td>
<td width="3%" valign="bottom" style="padding:0in 0in 0in 0in;width:3.44%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.22%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Power of Attorney (included on signature page)*</font></p>    </td>   </tr>  </table>
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<div style="margin:0in 0in .0001pt;"><hr size="1" width="25%" noshade color="black" align="left"></div>
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">* Filed herewith</font></p>
<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;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">[SIGNATURES ON THE NEXT PAGE]</font></b></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;">3<a name="PB_3_200028_5796"></a></font></p>
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<!-- SEQ.=1,FOLIO='3',FILE='C:\JMS\107311\13-10965-1\task6004461\10965-1-ba.htm',USER='107311',CD='Apr 28 20:00 2013' -->

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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;">SIGNATURES</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;text-indent:.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Pursuant to the requirements of the Securities Act, the Company certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form&nbsp;S-8 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in Research Triangle Park, North Carolina, on this 30</font><font size="1" style="font-size:6.5pt;position:relative;top:-3.0pt;">th</font><font size="2" style="font-size:10.0pt;">&#160;day of April, 2013.</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;">&nbsp;</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;">UNITED THERAPEUTICS CORPORATION</font></b></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;">&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: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;">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/   Martine A. Rothblatt</font></p>    </td>   </tr>
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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 style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Martine   A. Rothblatt, Ph.D.</font></p>    </td>   </tr>
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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 style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Chairman   of the Board and Chief Executive Officer</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;">POWER OF ATTORNEY</font></b></p>
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<p style="margin:0in 0in .0001pt;text-indent:.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">KNOW ALL MEN BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints Martine A. Rothblatt, Ph.D., John M. Ferrari and Paul A. Mahon, and each of them, with full power of substitution and full power to act without the others, his or her true and lawful attorney-in-fact and agent, to act for him or her and in his or her name, place and stead, in any and all capacities, to sign this Registration Statement on Form&nbsp;S-8 any and all amendments (including post-effective amendments) to this Registration Statement and any subsequent registration statement the Company may hereafter file with the Commission pursuant to Rule&nbsp;462(b)&nbsp;under the Securities Act to register additional Awards, and to file this Registration Statement and any subsequent registration statement and all amendments thereto, with all exhibits thereto, and other documents in connection therewith, with the Commission, granting unto such attorneys-in-fact and agents, full power and authority to do and perform each and every act and thing requisite and necessary to be done in and about the premises, as fully to all intents and purposes as he might or could do, and hereby ratifies and confirms all his said attorneys-in-fact and agents, or his substitute or substitutes, may lawfully do or cause to be done by virtue hereof.&#160; This Power of Attorney may be signed in any number of counterparts, each of which shall constitute an original and all of which, taken together, shall constitute one Power of Attorney.</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;text-indent:.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Pursuant to the requirements of the Securities Act, this Registration Statement has been signed below by the following persons in the capacities and on the date indicated.</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 align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="1" 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="1" face="Times New Roman" style="font-size:8.0pt;font-weight:bold;">Title</font></b></p>    </td>
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<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="1" 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="1" face="Times New Roman" style="font-size:8.0pt;font-weight:bold;">Date</font></b></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>
<td width="40%" valign="top" style="border:none;padding:0in 0in 0in 0in;width:40.12%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<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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<td width="36%" valign="top" style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 0in 0in;width:36.66%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">/s/   Martine A. Rothblatt</font></p>    </td>
<td width="3%" valign="top" style="padding:0in 0in 0in 0in;width:3.22%;">
<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 style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Chairman   of the Board and Chief</font></p>    </td>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="17%" valign="top" style="padding:0in 0in 0in 0in;width:17.78%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">April&nbsp;30,   2013</font></p>    </td>   </tr>
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<td width="36%" valign="top" style="border:none;padding:0in 0in 0in 0in;width:36.66%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Martine   A. Rothblatt, Ph.D.</font></p>    </td>
<td width="3%" valign="top" style="padding:0in 0in 0in 0in;width:3.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="40%" valign="top" style="padding:0in 0in 0in 0in;width:40.12%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Executive   Officer </font></p>    </td>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="17%" valign="top" style="padding:0in 0in 0in 0in;width:17.78%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&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:1.0pt;">&nbsp;</font></p>    </td>
<td width="3%" valign="top" style="padding:0in 0in 0in 0in;width:3.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="40%" valign="top" style="padding:0in 0in 0in 0in;width:40.12%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(Principal   Executive Officer)</font></p>    </td>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="17%" valign="top" style="padding:0in 0in 0in 0in;width:17.78%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&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;">&nbsp;</font></p>    </td>
<td width="3%" valign="top" style="padding:0in 0in 0in 0in;width:3.22%;">
<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>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="17%" valign="top" style="padding:0in 0in 0in 0in;width:17.78%;">
<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;">/s/   John M. Ferrari </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>
<td width="40%" valign="top" style="padding:0in 0in 0in 0in;width:40.12%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Chief   Financial Officer and</font></p>    </td>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="17%" valign="top" style="padding:0in 0in 0in 0in;width:17.78%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">April&nbsp;30,   2013</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;">John   M. Ferrari</font></p>    </td>
<td width="3%" valign="top" style="padding:0in 0in 0in 0in;width:3.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="40%" valign="top" style="padding:0in 0in 0in 0in;width:40.12%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Treasurer</font></p>    </td>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="17%" valign="top" style="padding:0in 0in 0in 0in;width:17.78%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>   </tr>
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<td width="36%" valign="top" style="padding:0in 0in 0in 0in;width:36.66%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="3%" valign="top" style="padding:0in 0in 0in 0in;width:3.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="40%" valign="top" style="padding:0in 0in 0in 0in;width:40.12%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(Principal   Financial Officer and</font></p>    </td>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="17%" valign="top" style="padding:0in 0in 0in 0in;width:17.78%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&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: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: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;">Principal   Accounting Officer)</font></p>    </td>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<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 style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>   </tr>  </table>
<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;">4<a name="PB_4_200028_2897"></a></font></p>
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<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="1" 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="1" face="Times New Roman" style="font-size:8.0pt;font-weight:bold;">Title</font></b></p>    </td>
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<p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="1" 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="1" face="Times New Roman" style="font-size:8.0pt;font-weight:bold;">Date</font></b></p>    </td>   </tr>
<tr>
<td width="36%" valign="top" style="border:none;padding:0in 0in 0in 0in;width:36.66%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="3%" valign="top" style="padding:0in 0in 0in 0in;width:3.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="40%" valign="top" style="border:none;padding:0in 0in 0in 0in;width:40.12%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="17%" valign="top" style="border:none;padding:0in 0in 0in 0in;width:17.78%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="36%" valign="top" style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 0in 0in;width:36.66%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">/s/   Roger A. Jeffs </font></p>    </td>
<td width="3%" valign="top" style="padding:0in 0in 0in 0in;width:3.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="40%" valign="top" style="padding:0in 0in 0in 0in;width:40.12%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">President,   Chief Operating Officer </font></p>    </td>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="17%" valign="top" style="padding:0in 0in 0in 0in;width:17.78%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">April&nbsp;30,   2013</font></p>    </td>   </tr>
<tr>
<td width="36%" valign="top" style="border:none;padding:0in 0in 0in 0in;width:36.66%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Roger   A. Jeffs, Ph.D.</font></p>    </td>
<td width="3%" valign="top" style="padding:0in 0in 0in 0in;width:3.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="40%" valign="top" style="padding:0in 0in 0in 0in;width:40.12%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">and   Director</font></p>    </td>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="17%" valign="top" style="padding:0in 0in 0in 0in;width:17.78%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="36%" valign="top" style="padding:0in 0in 0in 0in;width:36.66%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="3%" valign="top" style="padding:0in 0in 0in 0in;width:3.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="40%" valign="top" style="padding:0in 0in 0in 0in;width:40.12%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="17%" valign="top" style="padding:0in 0in 0in 0in;width:17.78%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="36%" valign="top" style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 0in 0in;width:36.66%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">/s/   Christopher Causey </font></p>    </td>
<td width="3%" valign="top" style="padding:0in 0in 0in 0in;width:3.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="40%" valign="top" style="padding:0in 0in 0in 0in;width:40.12%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Director</font></p>    </td>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="17%" valign="top" style="padding:0in 0in 0in 0in;width:17.78%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">April&nbsp;30,   2013</font></p>    </td>   </tr>
<tr>
<td width="36%" valign="top" style="border:none;padding:0in 0in 0in 0in;width:36.66%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Christopher   Causey</font></p>    </td>
<td width="3%" valign="top" style="padding:0in 0in 0in 0in;width:3.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="40%" valign="top" style="padding:0in 0in 0in 0in;width:40.12%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="17%" valign="top" style="padding:0in 0in 0in 0in;width:17.78%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="36%" valign="top" style="padding:0in 0in 0in 0in;width:36.66%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="3%" valign="top" style="padding:0in 0in 0in 0in;width:3.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="40%" valign="top" style="padding:0in 0in 0in 0in;width:40.12%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="17%" valign="top" style="padding:0in 0in 0in 0in;width:17.78%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="36%" valign="top" style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 0in 0in;width:36.66%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">/s/   Raymond A. Dwek </font></p>    </td>
<td width="3%" valign="top" style="padding:0in 0in 0in 0in;width:3.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="40%" valign="top" style="padding:0in 0in 0in 0in;width:40.12%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Director</font></p>    </td>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="17%" valign="top" style="padding:0in 0in 0in 0in;width:17.78%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">April&nbsp;30,   2013</font></p>    </td>   </tr>
<tr>
<td width="36%" valign="top" style="border:none;padding:0in 0in 0in 0in;width:36.66%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Raymond   A. Dwek, F.R.S.</font></p>    </td>
<td width="3%" valign="top" style="padding:0in 0in 0in 0in;width:3.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="40%" valign="top" style="padding:0in 0in 0in 0in;width:40.12%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="17%" valign="top" style="padding:0in 0in 0in 0in;width:17.78%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="36%" valign="top" style="padding:0in 0in 0in 0in;width:36.66%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="3%" valign="top" style="padding:0in 0in 0in 0in;width:3.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="40%" valign="top" style="padding:0in 0in 0in 0in;width:40.12%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="17%" valign="top" style="padding:0in 0in 0in 0in;width:17.78%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="36%" valign="top" style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 0in 0in;width:36.66%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">/s/   Richard Giltner </font></p>    </td>
<td width="3%" valign="top" style="padding:0in 0in 0in 0in;width:3.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="40%" valign="top" style="padding:0in 0in 0in 0in;width:40.12%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Director</font></p>    </td>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="17%" valign="top" style="padding:0in 0in 0in 0in;width:17.78%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">April&nbsp;30,   2013</font></p>    </td>   </tr>
<tr>
<td width="36%" valign="top" style="border:none;padding:0in 0in 0in 0in;width:36.66%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Richard   Giltner</font></p>    </td>
<td width="3%" valign="top" style="padding:0in 0in 0in 0in;width:3.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="40%" valign="top" style="padding:0in 0in 0in 0in;width:40.12%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="17%" valign="top" style="padding:0in 0in 0in 0in;width:17.78%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="36%" valign="top" style="padding:0in 0in 0in 0in;width:36.66%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="3%" valign="top" style="padding:0in 0in 0in 0in;width:3.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="40%" valign="top" style="padding:0in 0in 0in 0in;width:40.12%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="17%" valign="top" style="padding:0in 0in 0in 0in;width:17.78%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="36%" valign="top" style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 0in 0in;width:36.66%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">/s/   R. Paul Gray </font></p>    </td>
<td width="3%" valign="top" style="padding:0in 0in 0in 0in;width:3.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="40%" valign="top" style="padding:0in 0in 0in 0in;width:40.12%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Director</font></p>    </td>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="17%" valign="top" style="padding:0in 0in 0in 0in;width:17.78%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">April&nbsp;30,   2013</font></p>    </td>   </tr>
<tr>
<td width="36%" valign="top" style="border:none;padding:0in 0in 0in 0in;width:36.66%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">R.   Paul Gray</font></p>    </td>
<td width="3%" valign="top" style="padding:0in 0in 0in 0in;width:3.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="40%" valign="top" style="padding:0in 0in 0in 0in;width:40.12%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="17%" valign="top" style="padding:0in 0in 0in 0in;width:17.78%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="36%" valign="top" style="padding:0in 0in 0in 0in;width:36.66%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="3%" valign="top" style="padding:0in 0in 0in 0in;width:3.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="40%" valign="top" style="padding:0in 0in 0in 0in;width:40.12%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="17%" valign="top" style="padding:0in 0in 0in 0in;width:17.78%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="36%" valign="top" style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 0in 0in;width:36.66%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="3%" valign="top" style="padding:0in 0in 0in 0in;width:3.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="40%" valign="top" style="padding:0in 0in 0in 0in;width:40.12%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Director</font></p>    </td>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="17%" valign="top" style="padding:0in 0in 0in 0in;width:17.78%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">April&nbsp;30,   2013</font></p>    </td>   </tr>
<tr>
<td width="36%" valign="top" style="border:none;padding:0in 0in 0in 0in;width:36.66%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Raymond   Kurzweil</font></p>    </td>
<td width="3%" valign="top" style="padding:0in 0in 0in 0in;width:3.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="40%" valign="top" style="padding:0in 0in 0in 0in;width:40.12%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="17%" valign="top" style="padding:0in 0in 0in 0in;width:17.78%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="36%" valign="top" style="padding:0in 0in 0in 0in;width:36.66%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="3%" valign="top" style="padding:0in 0in 0in 0in;width:3.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="40%" valign="top" style="padding:0in 0in 0in 0in;width:40.12%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="17%" valign="top" style="padding:0in 0in 0in 0in;width:17.78%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="36%" valign="top" style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 0in 0in;width:36.66%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">/s/   Christopher Patusky </font></p>    </td>
<td width="3%" valign="top" style="padding:0in 0in 0in 0in;width:3.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="40%" valign="top" style="padding:0in 0in 0in 0in;width:40.12%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Director</font></p>    </td>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="17%" valign="top" style="padding:0in 0in 0in 0in;width:17.78%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">April&nbsp;30,   2013</font></p>    </td>   </tr>
<tr>
<td width="36%" valign="top" style="border:none;padding:0in 0in 0in 0in;width:36.66%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Christopher   Patusky</font></p>    </td>
<td width="3%" valign="top" style="padding:0in 0in 0in 0in;width:3.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="40%" valign="top" style="padding:0in 0in 0in 0in;width:40.12%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="17%" valign="top" style="padding:0in 0in 0in 0in;width:17.78%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="36%" valign="top" style="padding:0in 0in 0in 0in;width:36.66%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="3%" valign="top" style="padding:0in 0in 0in 0in;width:3.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="40%" valign="top" style="padding:0in 0in 0in 0in;width:40.12%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="17%" valign="top" style="padding:0in 0in 0in 0in;width:17.78%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="36%" valign="top" style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 0in 0in;width:36.66%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">/s/   Louis W. Sullivan </font></p>    </td>
<td width="3%" valign="top" style="padding:0in 0in 0in 0in;width:3.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="40%" valign="top" style="padding:0in 0in 0in 0in;width:40.12%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Director</font></p>    </td>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="17%" valign="top" style="padding:0in 0in 0in 0in;width:17.78%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">April&nbsp;30,   2013</font></p>    </td>   </tr>
<tr>
<td width="36%" valign="top" style="border:none;padding:0in 0in 0in 0in;width:36.66%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Louis   W. Sullivan, M.D.</font></p>    </td>
<td width="3%" valign="top" style="padding:0in 0in 0in 0in;width:3.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="40%" valign="top" style="padding:0in 0in 0in 0in;width:40.12%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="17%" valign="top" style="padding:0in 0in 0in 0in;width:17.78%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="36%" valign="top" style="padding:0in 0in 0in 0in;width:36.66%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="3%" valign="top" style="padding:0in 0in 0in 0in;width:3.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="40%" valign="top" style="padding:0in 0in 0in 0in;width:40.12%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="17%" valign="top" style="padding:0in 0in 0in 0in;width:17.78%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="36%" valign="top" style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 0in 0in;width:36.66%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">/s/   Tommy Thompson </font></p>    </td>
<td width="3%" valign="top" style="padding:0in 0in 0in 0in;width:3.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="40%" valign="top" style="padding:0in 0in 0in 0in;width:40.12%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Director</font></p>    </td>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="17%" valign="top" style="padding:0in 0in 0in 0in;width:17.78%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">April&nbsp;30,   2013</font></p>    </td>   </tr>
<tr>
<td width="36%" valign="top" style="border:none;padding:0in 0in 0in 0in;width:36.66%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Tommy   Thompson</font></p>    </td>
<td width="3%" valign="top" style="padding:0in 0in 0in 0in;width:3.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="40%" valign="top" style="padding:0in 0in 0in 0in;width:40.12%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="2%" valign="top" style="padding:0in 0in 0in 0in;width:2.22%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="17%" valign="top" style="padding:0in 0in 0in 0in;width:17.78%;">
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>   </tr>  </table>
<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;">5<a name="PB_5_200028_3020"></a></font></p>
<div style="margin:0in 0in .0001pt;"><hr size="3" width="100%" noshade color="#010101" align="left"></div>
</div>
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<div>
<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;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">EXHIBIT&nbsp;INDEX</font></b></p>
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
<table border="0" cellspacing="0" cellpadding="0" width="100%" style="border-collapse:collapse;width:100.0%;">
<tr>
<td width="11%" valign="bottom" style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 0in 0in;width:11.12%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><b><font size="1" face="Times New Roman" style="font-size:8.0pt;font-weight:bold;">Exhibit&nbsp;No.</font></b></p>    </td>
<td width="2%" valign="bottom" style="padding:0in 0in 0in 0in;width:2.52%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><b><font size="1" face="Times New Roman" style="font-size:1.0pt;font-weight:bold;">&nbsp;</font></b></p>    </td>
<td width="86%" valign="bottom" style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 0in 0in;width:86.36%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><b><font size="1" face="Times New Roman" style="font-size:8.0pt;font-weight:bold;">Description</font></b></p>    </td>   </tr>
<tr>
<td width="11%" valign="top" style="border:none;padding:0in 0in 0in 0in;width:11.12%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="2%" valign="bottom" style="padding:0in 0in 0in 0in;width:2.52%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="border:none;padding:0in 0in 0in 0in;width:86.36%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="11%" valign="top" style="padding:0in 0in 0in 0in;width:11.12%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">4.1</font></p>    </td>
<td width="2%" valign="bottom" style="padding:0in 0in 0in 0in;width:2.52%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.36%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Amended and Restated Certificate of Incorporation of the Company   (incorporated by reference to Exhibit&nbsp;3.1 of the Company&#146;s Registration   Statement on Form&nbsp;S-1 (Registration No.&nbsp;333-76409))</font></p>    </td>   </tr>
<tr>
<td width="11%" valign="top" style="padding:0in 0in 0in 0in;width:11.12%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="2%" valign="bottom" style="padding:0in 0in 0in 0in;width:2.52%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.36%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="11%" valign="top" style="padding:0in 0in 0in 0in;width:11.12%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">4.2</font></p>    </td>
<td width="2%" valign="bottom" style="padding:0in 0in 0in 0in;width:2.52%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.36%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Certificate of Amendment to Amended and Restated Certificate of   Incorporation of the Company (incorporated by reference to Exhibit&nbsp;3.1   of the Company&#146;s Current Report on Form&nbsp;8-K, filed on June&nbsp;28,   2010)</font></p>    </td>   </tr>
<tr>
<td width="11%" valign="top" style="padding:0in 0in 0in 0in;width:11.12%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="2%" valign="bottom" style="padding:0in 0in 0in 0in;width:2.52%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.36%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="11%" valign="top" style="padding:0in 0in 0in 0in;width:11.12%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">4.3</font></p>    </td>
<td width="2%" valign="bottom" style="padding:0in 0in 0in 0in;width:2.52%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.36%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Second Amended and Restated Bylaws of the Company, as amended   (incorporated by reference to Exhibit&nbsp;3.2 of the Company&#146;s Quarterly   Report on Form&nbsp;10-Q for the quarter ended March&nbsp;31, 2008)</font></p>    </td>   </tr>
<tr>
<td width="11%" valign="top" style="padding:0in 0in 0in 0in;width:11.12%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="2%" valign="bottom" style="padding:0in 0in 0in 0in;width:2.52%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.36%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="11%" valign="top" style="padding:0in 0in 0in 0in;width:11.12%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">5.1</font></p>    </td>
<td width="2%" valign="bottom" style="padding:0in 0in 0in 0in;width:2.52%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.36%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Opinion of counsel*</font></p>    </td>   </tr>
<tr>
<td width="11%" valign="top" style="padding:0in 0in 0in 0in;width:11.12%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="2%" valign="bottom" style="padding:0in 0in 0in 0in;width:2.52%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.36%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="11%" valign="top" style="padding:0in 0in 0in 0in;width:11.12%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">10.1</font></p>    </td>
<td width="2%" valign="bottom" style="padding:0in 0in 0in 0in;width:2.52%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.36%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">United Therapeutics Corporation 2011 Share Tracking Awards Plan   (incorporated by reference to Exhibit&nbsp;10.1 of the Company&#146;s Current   Report on Form&nbsp;8-K, filed on March&nbsp;18, 2011)</font></p>    </td>   </tr>
<tr>
<td width="11%" valign="top" style="padding:0in 0in 0in 0in;width:11.12%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="2%" valign="bottom" style="padding:0in 0in 0in 0in;width:2.52%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.36%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="11%" valign="top" style="padding:0in 0in 0in 0in;width:11.12%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">10.2</font></p>    </td>
<td width="2%" valign="bottom" style="padding:0in 0in 0in 0in;width:2.52%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.36%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">First Amendment to the United Therapeutics Corporation 2011 Share   Tracking Awards Plan, effective as of February&nbsp;1, 2012 (incorporated by   reference to Exhibit&nbsp;10.2 of the Company&#146;s Current Report on   Form&nbsp;8-K, filed on February&nbsp;6, 2012)</font></p>    </td>   </tr>
<tr>
<td width="11%" valign="top" style="padding:0in 0in 0in 0in;width:11.12%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="2%" valign="bottom" style="padding:0in 0in 0in 0in;width:2.52%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.36%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="11%" valign="top" style="padding:0in 0in 0in 0in;width:11.12%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">10.3</font></p>    </td>
<td width="2%" valign="bottom" style="padding:0in 0in 0in 0in;width:2.52%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.36%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Second Amendment to the United Therapeutics Corporation 2011 Share   Tracking Awards Plan, effective as of October&nbsp;30, 2012 (incorporated by   reference to Exhibit&nbsp;10.1 of the Company&#146;s Quarterly Report on   Form&nbsp;10-Q for the quarter ended September&nbsp;30, 2012)</font></p>    </td>   </tr>
<tr>
<td width="11%" valign="top" style="padding:0in 0in 0in 0in;width:11.12%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="2%" valign="bottom" style="padding:0in 0in 0in 0in;width:2.52%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.36%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="11%" valign="top" style="padding:0in 0in 0in 0in;width:11.12%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">10.4</font></p>    </td>
<td width="2%" valign="bottom" style="padding:0in 0in 0in 0in;width:2.52%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.36%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Third Amendment to the United Therapeutics Corporation 2011 Share   Tracking Awards Plan, effective as of February&nbsp;1, 2013 (incorporated by   reference to Exhibit&nbsp;10.1 of the Company&#146;s Current Report on   Form&nbsp;8-K, filed on February&nbsp;4, 2013)</font></p>    </td>   </tr>
<tr>
<td width="11%" valign="top" style="padding:0in 0in 0in 0in;width:11.12%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="2%" valign="bottom" style="padding:0in 0in 0in 0in;width:2.52%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.36%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="11%" valign="top" style="padding:0in 0in 0in 0in;width:11.12%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">10.5</font></p>    </td>
<td width="2%" valign="bottom" style="padding:0in 0in 0in 0in;width:2.52%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.36%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Form&nbsp;of Terms and Conditions for Awards to Employees   (incorporated by reference to Exhibit&nbsp;10.2 of the Company&#146;s Registration   Statement on Form&nbsp;S-8, filed on May&nbsp;2, 2011 (Registration   No.&nbsp;333-173858))</font></p>    </td>   </tr>
<tr>
<td width="11%" valign="top" style="padding:0in 0in 0in 0in;width:11.12%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="2%" valign="bottom" style="padding:0in 0in 0in 0in;width:2.52%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.36%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="11%" valign="top" style="padding:0in 0in 0in 0in;width:11.12%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">10.6</font></p>    </td>
<td width="2%" valign="bottom" style="padding:0in 0in 0in 0in;width:2.52%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.36%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Form&nbsp;of Terms and Conditions for Awards to Non-Employees   (incorporated by reference to Exhibit&nbsp;10.3 of the Company&#146;s Current   Report on Form&nbsp;8-K, filed on March&nbsp;18, 2011)</font></p>    </td>   </tr>
<tr>
<td width="11%" valign="top" style="padding:0in 0in 0in 0in;width:11.12%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="2%" valign="bottom" style="padding:0in 0in 0in 0in;width:2.52%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.36%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="11%" valign="top" style="padding:0in 0in 0in 0in;width:11.12%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">10.7</font></p>    </td>
<td width="2%" valign="bottom" style="padding:0in 0in 0in 0in;width:2.52%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.36%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Form&nbsp;of Grant Letter used by Registrant (incorporated by   reference to Exhibit&nbsp;10.4 of the Company&#146;s Current Report on   Form&nbsp;8-K, filed on March&nbsp;18, 2011)</font></p>    </td>   </tr>
<tr>
<td width="11%" valign="top" style="padding:0in 0in 0in 0in;width:11.12%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="2%" valign="bottom" style="padding:0in 0in 0in 0in;width:2.52%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.36%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="11%" valign="top" style="padding:0in 0in 0in 0in;width:11.12%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">23.1</font></p>    </td>
<td width="2%" valign="bottom" style="padding:0in 0in 0in 0in;width:2.52%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.36%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Consent of Independent Registered Public Accounting Firm*</font></p>    </td>   </tr>
<tr>
<td width="11%" valign="top" style="padding:0in 0in 0in 0in;width:11.12%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="2%" valign="bottom" style="padding:0in 0in 0in 0in;width:2.52%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.36%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="11%" valign="top" style="padding:0in 0in 0in 0in;width:11.12%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">23.2</font></p>    </td>
<td width="2%" valign="bottom" style="padding:0in 0in 0in 0in;width:2.52%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.36%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Consent of counsel (included in Exhibit&nbsp;5.1)*</font></p>    </td>   </tr>
<tr>
<td width="11%" valign="top" style="padding:0in 0in 0in 0in;width:11.12%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="2%" valign="bottom" style="padding:0in 0in 0in 0in;width:2.52%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.36%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>    </td>   </tr>
<tr>
<td width="11%" valign="top" style="padding:0in 0in 0in 0in;width:11.12%;">
<p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">24</font></p>    </td>
<td width="2%" valign="bottom" style="padding:0in 0in 0in 0in;width:2.52%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>    </td>
<td width="86%" valign="top" style="padding:0in 0in 0in 0in;width:86.36%;">
<p style="margin:0in 0in .0001pt;punctuation-wrap:simple;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Power of Attorney (included on signature page)*</font></p>    </td>   </tr>  </table>
<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>
<div style="margin:0in 0in .0001pt;"><hr size="1" width="25%" noshade color="black" align="left"></div>
<p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">* Filed herewith</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 align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">6<a name="PB_6_200028_7748"></a></font></p>
<div style="margin:0in 0in .0001pt;"><hr size="3" width="100%" noshade color="#010101" align="left"></div>
</div>
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{"company-data": {"conformed-name": "UNITED THERAPEUTICS Corp", "cik": "0001082554", "assigned-sic": "2834", "irs-number": "521984749", "state-of-incorporation": "DE", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-188241", "film-number": "13797392"}, "business-address": {"street1": "1040 SPRING ST", "city": "SILVER SPRING", "state": "MD", "zip": "20910", "phone": "3016089292"}, "mail-address": {"street1": "1040 SPRING ST", "city": "SILVER SPRING", "state": "MD", "zip": "20910"}, "former-company": {"former-conformed-name": "UNITED THERAPEUTICS CORP", "date-changed": "19990324"}}
As filed with the Securities and Exchange Commission on April 30, 2013
Registration No. 333-
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C.  20549
FORM S-8
REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933
United Therapeutics Corporation
(Exact Name of Registrant as Specified in the Charter)
Delaware
52-1984749
(State or other jurisdiction of incorporation
or organization)
(I.R.S. Employer Identification No.)
1040 Spring Street
Silver Spring, MD
20910
(Address of principal executive offices)
(Zip Code)
UNITED THERAPEUTICS CORPORATION
2011 SHARE TRACKING AWARDS PLAN
(Full title of the plan)
Martine A. Rothblatt, Chairman and Chief Executive Officer
United Therapeutics Corporation
1040 Spring Street
Silver Spring, MD 20910
(301) 608-9292
(Name, address and telephone number, including area code, of agent for service)
Copy to:
Stephen I. Glover, Esq.
John S. Hess, Jr., Esq.
Gibson, Dunn & Crutcher LLP
Vice President and Associate General   Counsel
1050 Connecticut Avenue, N.W.
United Therapeutics Corporation
Washington, D.C. 20036
1735 Connecticut Avenue, N.W.
(202) 955-8500
Washington, D.C. 20009
(202) 483-7000
Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company.  See the definitions of "large accelerated filer," "accelerated filer" and "smaller reporting company" in Rule 12b-2 of the Exchange Act.
Large accelerated filer
x
Accelerated filer
o
Non-accelerated filer
o
(Do not check if a   smaller reporting company)
Smaller reporting company
o
CALCULATION OF REGISTRATION FEE
Title of
Securities to be
Registered
Amount to be
Registered
Proposed Maximum
Offering Price Per Share (3)
Proposed Maximum
Aggregate Offering
Price (3)
Amount of
Registration
Fee
Share Tracking Awards (1) (2)
3,200,000 awards
$
60.455
$
193,456,000
$
26,387.40
(1)
This Registration Statement relates to share tracking awards that may be issued under the United Therapeutics Corporation 2011 Share Tracking Awards Plan.
(2)
Pursuant to Rule 416 under the Securities Act of 1933 (the "Securities Act"), this Registration Statement shall also cover any additional securities in respect of the securities identified in the above table as a result of any stock dividend, stock split, recapitalization or other similar transactions.
(3)
Estimated solely for the purpose of calculating the amount of the registration fee pursuant to Rule 457(h)(1) under the Securities Act. The price per share and aggregate offering price are based upon the average of the high and low prices of the Registrant's common stock as reported on the NASDAQ Global Select Market for April 25, 2013.
INTRODUCTION
This Registration Statement on Form S-8 is filed by United Therapeutics Corporation, a Delaware corporation (the "Company" or the "Registrant"), to register an additional 3,200,000 share tracking awards (the "Awards"), which have been and will be granted in accordance with the terms of the United Therapeutics 2011 Share Tracking Awards Plan (the "Plan").  Each award represents a contractual right to receive an amount in cash equal to the positive difference, if any, between the fair market value of the Award on the exercise date and the fair market value of the Award on the grant date.  The fair market value of an Award on the grant date or the exercise date is equal to the closing price per share of the Company's common stock on that date.
The Company previously filed with the Securities and Exchange Commission (the "Commission"): (a) a registration statement on Form S-8 (File No. 333-173858) on May 2, 2011 registering 2,000,000 Awards under the Plan and (b) a registration statement on Form S-8 (File No. 333-179746) on February 28, 2012 registering an additional 2,000,000 Awards under the Plan (together, the "Prior Registration Statements").  On October 30, 2012 and February 1, 2013, a majority of the Company's Board of Directors, in each case acting upon the recommendation of its Compensation Committee, approved amendments to the Plan to increase the maximum number of Awards available for grant under the Plan by 1,800,000 and 1,400,000 Awards, respectively (the "Second Amendment" and "Third Amendment," respectively), raising the total number of Awards available for grant under the Plan to 7,200,000 Awards.  The Second Amendment is described in the Company's Quarterly Report on Form 10-Q, filed with the Commission on November 1, 2012, and is filed as Exhibit 10.1 thereto.  The Third Amendment is described in the Company's Current Report on Form 8-K, filed with the Commission on February 4, 2013, and is filed as Exhibit 10.1 thereto.  The Plan was originally filed with the Commission on March 18, 2011 as Exhibit 10.1 to the Company's Current Report on Form 8-K.
In accordance with General Instruction E of Form S-8, the entire contents of the Prior Registration Statements are incorporated herein by reference, and certain information required by Part II is omitted.
PART I
INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS
Item 1.
Plan Information
*
Item 2.
Registrant Information and Employee Plan Annual Information
*
*
Information required by Part I to be contained in the Section 10(a) prospectus is omitted from this Registration Statement in accordance with Rule 428 under the Securities Act and the Note to Part I of Form S-8.
PART II
INFORMATION REQUIRED IN THE REGISTRATION STATEMENT
Item 3.
Incorporation of Documents by Reference
The following documents, which have heretofore been filed by the Company with the Commission
1
pursuant to the Securities Act, and pursuant to the Securities Exchange Act of 1934, as amended (the "Exchange Act"), are incorporated by reference herein and shall be deemed to be a part hereof:
(1)
The Annual Report on Form 10-K for the fiscal year ended December 31, 2012, which the Company filed with the Commission on February 26, 2013; and
(2)
All other reports filed pursuant to Section 13(a) or 15(d) of the Exchange Act since the end of the fiscal year covered by the Company's Annual Report referred to in (1) above.
In addition, all documents filed by the Company or the Plan pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act prior to the filing of a post-effective amendment to this Registration Statement which indicates that all securities offered hereby have been sold or which deregisters all such securities then remaining unsold, shall be deemed to be incorporated by reference in this Registration Statement and made a part hereof from their respective dates of filing (such documents, and the documents listed above, being hereinafter referred to as "Incorporated Documents"); provided, however, that the documents listed above or subsequently filed by the Company or the Plan pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act in each year during which the offering made by this Registration Statement is in effect prior to the filing with the Commission of the Company's Annual Report on Form 10-K covering such year shall cease to be Incorporated Documents or to be incorporated by reference in this Registration Statement from and after the filing of such Annual Reports.
Any statement contained herein shall be deemed to be modified or superseded for purposes of this Registration Statement to the extent that a statement contained in any subsequently filed Incorporated Document modifies or supersedes such statement.  Any statement contained in an Incorporated Document shall be deemed to be modified or superseded for purposes of this Registration Statement to the extent that a statement contained herein or in any other subsequently filed Incorporated Document modifies or supersedes such statement.  Any such statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this Registration Statement.
The Company's Exchange Act file number with the Commission is 000-26301.
Item 8.
Exhibits
Exhibit No.
Description
4.1
Amended and Restated Certificate of Incorporation of the Company   (incorporated by reference to Exhibit 3.1 of the Company's Registration   Statement on Form S-1 (Registration No. 333-76409))
4.2
Certificate of Amendment to Amended and Restated Certificate of   Incorporation of the Company (incorporated by reference to Exhibit 3.1   of the Company's Current Report on Form 8-K, filed on June 28,   2010)
4.3
Second Amended and Restated Bylaws of the Company, as amended   (incorporated by reference to Exhibit 3.2 of the Company's Quarterly   Report on Form 10-Q for the quarter ended March 31, 2008)
5.1
Opinion of counsel*
2
10.1
United Therapeutics Corporation 2011 Share Tracking Awards Plan   (incorporated by reference to Exhibit 10.1 of the Company's Current   Report on Form 8-K, filed on March 18, 2011)
10.2
First Amendment to the United Therapeutics Corporation 2011 Share   Tracking Awards Plan, effective as of February 1, 2012 (incorporated by   reference to Exhibit 10.2 of the Company's Current Report on   Form 8-K, filed on February 6, 2012)
10.3
Second Amendment to the United Therapeutics Corporation 2011 Share   Tracking Awards Plan, effective as of October 30, 2012 (incorporated by   reference to Exhibit 10.1 of the Company's Quarterly Report on   Form 10-Q for the quarter ended September 30, 2012)
10.4
Third Amendment to the United Therapeutics Corporation 2011 Share   Tracking Awards Plan, effective as of February 1, 2013 (incorporated by   reference to Exhibit 10.1 of the Company's Current Report on   Form 8-K, filed on February 4, 2013)
10.5
Form of Terms and Conditions for Awards to Employees   (incorporated by reference to Exhibit 10.2 of the Company's Registration   Statement on Form S-8, filed on May 2, 2011 (Registration   No. 333-173858))
10.6
Form of Terms and Conditions for Awards to Non-Employees   (incorporated by reference to Exhibit 10.3 of the Company's Current   Report on Form 8-K, filed on March 18, 2011)
10.7
Form of Grant Letter used by Registrant (incorporated by   reference to Exhibit 10.4 of the Company's Current Report on   Form 8-K, filed on March 18, 2011)
23.1
Consent of Independent Registered Public Accounting Firm*
23.2
Consent of counsel (included in Exhibit 5.1)*
24
Power of Attorney (included on signature page)*
* Filed herewith
[SIGNATURES ON THE NEXT PAGE]
3
SIGNATURES
Pursuant to the requirements of the Securities Act, the Company certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in Research Triangle Park, North Carolina, on this 30
th
day of April, 2013.
UNITED THERAPEUTICS CORPORATION
By:
/s/   Martine A. Rothblatt
Martine   A. Rothblatt, Ph.D.
Chairman   of the Board and Chief Executive Officer
POWER OF ATTORNEY
KNOW ALL MEN BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints Martine A. Rothblatt, Ph.D., John M. Ferrari and Paul A. Mahon, and each of them, with full power of substitution and full power to act without the others, his or her true and lawful attorney-in-fact and agent, to act for him or her and in his or her name, place and stead, in any and all capacities, to sign this Registration Statement on Form S-8 any and all amendments (including post-effective amendments) to this Registration Statement and any subsequent registration statement the Company may hereafter file with the Commission pursuant to Rule 462(b) under the Securities Act to register additional Awards, and to file this Registration Statement and any subsequent registration statement and all amendments thereto, with all exhibits thereto, and other documents in connection therewith, with the Commission, granting unto such attorneys-in-fact and agents, full power and authority to do and perform each and every act and thing requisite and necessary to be done in and about the premises, as fully to all intents and purposes as he might or could do, and hereby ratifies and confirms all his said attorneys-in-fact and agents, or his substitute or substitutes, may lawfully do or cause to be done by virtue hereof.  This Power of Attorney may be signed in any number of counterparts, each of which shall constitute an original and all of which, taken together, shall constitute one Power of Attorney.
Pursuant to the requirements of the Securities Act, this Registration Statement has been signed below by the following persons in the capacities and on the date indicated.
Name
Title
Date
/s/   Martine A. Rothblatt
Chairman   of the Board and Chief
April 30,   2013
Martine   A. Rothblatt, Ph.D.
Executive   Officer
(Principal   Executive Officer)
/s/   John M. Ferrari
Chief   Financial Officer and
April 30,   2013
John   M. Ferrari
Treasurer
(Principal   Financial Officer and
Principal   Accounting Officer)
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Name
Title
Date
/s/   Roger A. Jeffs
President,   Chief Operating Officer
April 30,   2013
Roger   A. Jeffs, Ph.D.
and   Director
/s/   Christopher Causey
Director
April 30,   2013
Christopher   Causey
/s/   Raymond A. Dwek
Director
April 30,   2013
Raymond   A. Dwek, F.R.S.
/s/   Richard Giltner
Director
April 30,   2013
Richard   Giltner
/s/   R. Paul Gray
Director
April 30,   2013
R.   Paul Gray
Director
April 30,   2013
Raymond   Kurzweil
/s/   Christopher Patusky
Director
April 30,   2013
Christopher   Patusky
/s/   Louis W. Sullivan
Director
April 30,   2013
Louis   W. Sullivan, M.D.
/s/   Tommy Thompson
Director
April 30,   2013
Tommy   Thompson
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EXHIBIT INDEX
Exhibit No.
Description
4.1
Amended and Restated Certificate of Incorporation of the Company   (incorporated by reference to Exhibit 3.1 of the Company's Registration   Statement on Form S-1 (Registration No. 333-76409))
4.2
Certificate of Amendment to Amended and Restated Certificate of   Incorporation of the Company (incorporated by reference to Exhibit 3.1   of the Company's Current Report on Form 8-K, filed on June 28,   2010)
4.3
Second Amended and Restated Bylaws of the Company, as amended   (incorporated by reference to Exhibit 3.2 of the Company's Quarterly   Report on Form 10-Q for the quarter ended March 31, 2008)
5.1
Opinion of counsel*
10.1
United Therapeutics Corporation 2011 Share Tracking Awards Plan   (incorporated by reference to Exhibit 10.1 of the Company's Current   Report on Form 8-K, filed on March 18, 2011)
10.2
First Amendment to the United Therapeutics Corporation 2011 Share   Tracking Awards Plan, effective as of February 1, 2012 (incorporated by   reference to Exhibit 10.2 of the Company's Current Report on   Form 8-K, filed on February 6, 2012)
10.3
Second Amendment to the United Therapeutics Corporation 2011 Share   Tracking Awards Plan, effective as of October 30, 2012 (incorporated by   reference to Exhibit 10.1 of the Company's Quarterly Report on   Form 10-Q for the quarter ended September 30, 2012)
10.4
Third Amendment to the United Therapeutics Corporation 2011 Share   Tracking Awards Plan, effective as of February 1, 2013 (incorporated by   reference to Exhibit 10.1 of the Company's Current Report on   Form 8-K, filed on February 4, 2013)
10.5
Form of Terms and Conditions for Awards to Employees   (incorporated by reference to Exhibit 10.2 of the Company's Registration   Statement on Form S-8, filed on May 2, 2011 (Registration   No. 333-173858))
10.6
Form of Terms and Conditions for Awards to Non-Employees   (incorporated by reference to Exhibit 10.3 of the Company's Current   Report on Form 8-K, filed on March 18, 2011)
10.7
Form of Grant Letter used by Registrant (incorporated by   reference to Exhibit 10.4 of the Company's Current Report on   Form 8-K, filed on March 18, 2011)
23.1
Consent of Independent Registered Public Accounting Firm*
23.2
Consent of counsel (included in Exhibit 5.1)*
24
Power of Attorney (included on signature page)*
* Filed herewith
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