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 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>As filed with the Securities and Exchange Commission on March 6, 2015 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="right"><B>Registration No.&nbsp;333-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </B></P>
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<P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P> <P STYLE="margin-top:4pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>UNITED STATES </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>SECURITIES AND EXCHANGE COMMISSION </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B>Washington, D.C. 20549 </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>FORM S-8
</B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>REGISTRATION STATEMENT </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B><I>UNDER </I></B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B><I>THE
SECURITIES ACT OF 1933 </I></B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center> <P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:24pt; font-family:Times New Roman" ALIGN="center"><B>Tetraphase Pharmaceuticals, Inc. </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>(Exact name of registrant as specified in its charter) </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD VALIGN="top" ALIGN="center"><B>Delaware</B></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="top" ALIGN="center"><B>20-5276217</B></TD></TR>
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<TD VALIGN="top" ALIGN="center"><B>(State or other jurisdiction of<BR>incorporation or organization)</B></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center"><B>(I.R.S. Employer<BR>Identification No.)</B></TD></TR>
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<TD VALIGN="top" ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>480 Arsenal Street, Suite 110,</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Watertown, MA</B></P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center"><B>02472</B></TD></TR>
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<TD VALIGN="top" ALIGN="center"><B>(Address of Principal Executive Offices)</B></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center"><B>(Zip Code)</B></TD></TR>
</TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>2013 Stock Incentive Plan </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(Full title of the plan) </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Guy Macdonald </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>President
and Chief Executive Officer </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>480 Arsenal Street, Suite 110, </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Watertown, MA 02472 </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(Name
and address of agent for service) </B></P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>(617) 715-3600 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(Telephone number, including area code, of agent for service) </B></P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center> <P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">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 &#147;large accelerated filer,&#148; &#147;accelerated filer&#148; and &#147;smaller reporting company&#148; in Rule 12b-2 of the Exchange Act. </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD VALIGN="bottom">Large&nbsp;accelerated&nbsp;filer</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"><FONT STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">Accelerated filer</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"><FONT STYLE="FONT-FAMILY:WINGDINGS">&#120;</FONT></TD></TR>
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<TD HEIGHT="8"></TD>
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<TD HEIGHT="8" COLSPAN="2"></TD>
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<TD VALIGN="bottom">Non-accelerated filer</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"><FONT STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT>&nbsp;&nbsp;(Do not check if a smaller reporting company)</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">Smaller&nbsp;reporting&nbsp;company</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"><FONT STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></TD></TR>
</TABLE> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center> <P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>CALCULATION OF REGISTRATION FEE </B></P> <P STYLE="font-size:4pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD COLSPAN="9" VALIGN="bottom"> <P STYLE="border-top:1.00px solid #000000">&nbsp;</P></TD></TR>
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<TD VALIGN="bottom" ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"><B>Title of securities<BR>to be registered</B></TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"><B>Amount<BR>to be<BR>registered(1)</B></TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"><B>Proposed<BR>maximum<BR>offering&nbsp;price<BR>per&nbsp;share</B></TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"><B>Proposed<BR>maximum<BR>aggregate<BR>offering&nbsp;price</B></TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"><B>Amount&nbsp;of<BR>registration fee</B></TD></TR>
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<TD VALIGN="top" STYLE="BORDER-TOP:1px solid #000000"> <P STYLE="margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman">Common Stock, $0.001 par value per share</P></TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000">1,232,232&nbsp;shares&nbsp;(2)</TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000">$39.56&nbsp;(3)</TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000">$48,747,097.92&nbsp;(3)</TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000">$5,665</TD></TR>
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<TD COLSPAN="9" VALIGN="bottom"> <P STYLE="border-top:1.00px solid #000000">&nbsp;</P></TD></TR>
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<TD COLSPAN="9" VALIGN="bottom"> <P STYLE="border-top:1.00px solid #000000">&nbsp;</P></TD></TR>
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<TD WIDTH="4%" VALIGN="top" ALIGN="left">(1)</TD>
<TD ALIGN="left" VALIGN="top">In accordance with Rule 416 under the Securities Act of 1933, as amended, this registration statement shall be deemed to cover any additional securities that may from time to time be offered or issued to prevent
dilution resulting from stock splits, reverse stock splits, stock dividends, recapitalizations or similar transactions. </TD></TR></TABLE>
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<TD WIDTH="4%" VALIGN="top" ALIGN="left">(2)</TD>
<TD ALIGN="left" VALIGN="top">Represents additional shares of Common Stock authorized for issuance under the 2013 Stock Incentive Plan. </TD></TR></TABLE>
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<TD WIDTH="4%" VALIGN="top" ALIGN="left">(3)</TD>
<TD ALIGN="left" VALIGN="top">Estimated solely for the purpose of calculating the registration fee pursuant to Rules 457(c) and 457(h) of the Securities Act of 1933, as amended. The price per share and aggregate offering price are calculated on the
basis of (i)&nbsp;$39.79, the weighted average exercise price of the 820,103 shares covered by this registration statement that are subject to outstanding stock option grants under the 2013 Stock Incentive Plan, at prices ranging from $35.20 to
$42.70, and (ii)&nbsp;$39.10, the average of the high and low prices of the Registrant&#146;s Common Stock as reported on the NASDAQ Global Market on March&nbsp;2, 2015 with respect to the 412,129 shares covered by this registration statement
issuable under the 2013 Stock Incentive Plan that are not subject to outstanding awards. </TD></TR></TABLE> <P STYLE="font-size:10pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<P STYLE="line-height:1.0pt;margin-top:0pt;margin-bottom:0pt;border-bottom:1px solid #000000">&nbsp;</P> <P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P>

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 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Statement of Incorporation by Reference </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">This Registration Statement on Form S-8 is being filed to register the offer and sale of an additional 1,232,232 shares of Common Stock,
$0.001 par value per share, of Tetraphase Pharmaceuticals, Inc. (the &#147;Registrant&#148;) authorized for issuance under the 2013 Stock Incentive Plan (the &#147;2013 Plan&#148;) of the Registrant. Pursuant to General Instruction E to Form S-8,
except as otherwise set forth below, this Registration Statement incorporates by reference the contents of the Registration Statement on Form S-8 filed by the Registrant on June&nbsp;14, 2013 (File No.&nbsp;333- 189361) relating to the 2013 Plan.
</P> <P STYLE="margin-top:24pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>PART II </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>INFORMATION REQUIRED IN THE REGISTRATION STATEMENT </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; margin-left:4%; font-size:10pt; font-family:Times New Roman"><B>Item&nbsp;8. Exhibits. </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">The Index to Exhibits immediately preceding the exhibits is incorporated herein by reference. </P>
 <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">- 1 - </P>


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 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>SIGNATURES </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:8%; font-size:10pt; font-family:Times New Roman">Pursuant to the requirements of the Securities Act of 1933, the registrant 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 the city of Watertown, the Commonwealth of Massachusetts, on this 6<SUP
STYLE="font-size:85%; vertical-align:top">th</SUP> day of March, 2015. </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><DIV ALIGN="right">
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<TD VALIGN="top" COLSPAN="3"><B>TETRAPHASE PHARMACEUTICALS, INC.</B></TD></TR>
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<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
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<TD VALIGN="top"> <P STYLE="margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman">By:</P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Guy Macdonald</P></TD></TR>
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<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">Guy Macdonald</TD></TR>
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<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">President and Chief Executive Officer</TD></TR>
</TABLE></DIV> <P STYLE="margin-top:24pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>POWER OF ATTORNEY AND SIGNATURES </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:8%; font-size:10pt; font-family:Times New Roman">We, the undersigned officers and directors of Tetraphase Pharmaceuticals, Inc., hereby severally constitute and appoint Guy Macdonald and
David Lubner, and each of them singly, our true and lawful attorneys with full power to them, and each of them singly, to sign for us and in our names in the capacities indicated below, the registration statement on Form S-8 filed herewith and any
and all subsequent amendments to said registration statement, and generally to do all such things in our names and on our behalf in our capacities as officers and directors to enable Tetraphase Pharmaceuticals, Inc. to comply with the provisions of
the Securities Act of 1933, as amended, and all requirements of the Securities and Exchange Commission, hereby ratifying and confirming our signatures as they may be signed by our said attorneys, or any of them, to said registration statement and
any and all amendments thereto. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:8%; font-size:10pt; font-family:Times New Roman">Pursuant to the requirements of the Securities Act of 1933, this registration statement has been signed
by the following persons in the capacities and on the dates indicated. </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD VALIGN="bottom" NOWRAP ALIGN="center"> <P STYLE="border-bottom:1.00pt solid #000000; width:33.30pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Signature</B></P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center"> <P STYLE="border-bottom:1.00pt solid #000000; width:15.95pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Title</B></P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center"> <P STYLE="border-bottom:1.00pt solid #000000; width:16.00pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Date</B></P></TD></TR>


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<TD VALIGN="bottom"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Guy Macdonald</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="middle" ROWSPAN="2">President and Chief Executive Officer, Director (Principal Executive Officer)</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ROWSPAN="2">March 6, 2015</TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">Guy Macdonald</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD></TR>
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<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
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<TD VALIGN="bottom"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ David C. Lubner</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="middle" ROWSPAN="2">Senior Vice President and Chief Financial Officer (Principal Financial Officer and Principal Accounting Officer)</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ROWSPAN="2">March 6, 2015</TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">David C. Lubner</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD></TR>
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<TD HEIGHT="16"></TD>
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<TD VALIGN="bottom"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ L. Patrick Gage</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="middle" ROWSPAN="2">Director</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ROWSPAN="2">March 6,&nbsp;2015</TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">L. Patrick Gage</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Garen Bohlin</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="middle" ROWSPAN="2">Director</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ROWSPAN="2">March 6, 2015</TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">Garen Bohlin</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD></TR></TABLE>

<p Style='page-break-before:always'>
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<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt">


<TR>
<TD WIDTH="37%"></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="44%"></TD>
<TD VALIGN="bottom" WIDTH="2%"></TD>
<TD WIDTH="15%"></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>

<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Jeffrey Chodakewitz</P></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="middle" ROWSPAN="2" NOWRAP>Director</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom" ROWSPAN="2">March 6, 2015</TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">Jeffrey Chodakewitz</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ John G. Freund</P></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="middle" ROWSPAN="2">Director</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom" ROWSPAN="2">March 6, 2015</TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">John G. Freund</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Steven R. Gullans</P></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="middle" ROWSPAN="2">Director</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom" ROWSPAN="2">March 6, 2015</TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">Steven R. Gullans</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Nancy Wysenski</P></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="middle" ROWSPAN="2">Director</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom" ROWSPAN="2">March 6, 2015</TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">Nancy Wysenski</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD></TR>
</TABLE>

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 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>INDEX TO EXHIBITS </B></P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TR>
<TD></TD>
<TD VALIGN="bottom" WIDTH="6%"></TD>
<TD WIDTH="92%"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:8pt">
<TD VALIGN="bottom" NOWRAP ALIGN="center"> <P STYLE="border-bottom:1.00pt solid #000000; width:26.20pt; font-size:8pt; font-family:Times New Roman" ALIGN="center">Number</P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP> <P STYLE="border-bottom:1.00pt solid #000000; width:37.25pt; font-size:8pt; font-family:Times New Roman">Description</P></TD></TR>


<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>4.1(1)</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Restated Certificate of Incorporation of the Registrant</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>4.2(1)</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Amended and Restated Bylaws of the Registrant</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>5.1</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Opinion of Wilmer Cutler Pickering Hale and Dorr LLP, counsel to the Registrant</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>23.1</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Consent of Wilmer Cutler Pickering Hale and Dorr LLP</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">(included in Exhibit 5.1)</P></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>23.2</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Consent of Ernst &amp; Young LLP</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>24.1</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Power of attorney (included on the signature pages of this registration statement)</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>99.1(2)</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">2013 Stock Incentive Plan</TD></TR>
</TABLE> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TR>
<TD WIDTH="4%" VALIGN="top" ALIGN="left">(1)</TD>
<TD ALIGN="left" VALIGN="top">Incorporated by reference to the exhibit to the Registrant&#146;s quarterly report on Form 10-Q filed with the SEC on May&nbsp;13, 2013. </TD></TR></TABLE>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="4%" VALIGN="top" ALIGN="left">(2)</TD>
<TD ALIGN="left" VALIGN="top">Incorporated by reference to the Registrant&#146;s registration statement on Form S-1/A, filed with the Securities and Exchange Commission on March&nbsp;5, 2013. </TD></TR></TABLE>
</BODY></HTML>
[{"type": "S-8", "sequence": "1", "filename": "d882519ds8.htm", "description": "FORM S-8", "secsgml_size_bytes": 29967}]
{"company-data": {"conformed-name": "TETRAPHASE PHARMACEUTICALS INC", "cik": "0001373707", "assigned-sic": "2834", "irs-number": "000000000", "state-of-incorporation": "DE", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-202576", "film-number": "15682007"}, "business-address": {"street1": "480 ARSENAL STREET", "street2": "SUITE 110", "city": "WATERTOWN", "state": "MA", "zip": "02472", "phone": "617.715.3600"}, "mail-address": {"street1": "480 ARSENAL STREET", "street2": "SUITE 110", "city": "WATERTOWN", "state": "MA", "zip": "02472"}}
Form S-8
As filed with the Securities and Exchange Commission on March 6, 2015
Registration No. 333-
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM S-8
REGISTRATION STATEMENT
UNDER
THE
SECURITIES ACT OF 1933
Tetraphase Pharmaceuticals, Inc.
(Exact name of registrant as specified in its charter)
Delaware
20-5276217
(State or other jurisdiction of
incorporation or organization)
(I.R.S. Employer
Identification No.)
480 Arsenal Street, Suite 110,
Watertown, MA
02472
(Address of Principal Executive Offices)
(Zip Code)
2013 Stock Incentive Plan
(Full title of the plan)
Guy Macdonald
President
and Chief Executive Officer
480 Arsenal Street, Suite 110,
Watertown, MA 02472
(Name
and address of agent for service)
(617) 715-3600
(Telephone number, including area code, of agent for service)
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
¨
Accelerated filer
x
Non-accelerated filer
¨
(Do not check if a smaller reporting company)
Smaller reporting company
¨
CALCULATION OF REGISTRATION FEE
Title of securities
to be registered
Amount
to be
registered(1)
Proposed
maximum
offering price
per share
Proposed
maximum
aggregate
offering price
Amount of
registration fee
Common Stock, $0.001 par value per share
1,232,232 shares (2)
$39.56 (3)
$48,747,097.92 (3)
$5,665
(1)
In accordance with Rule 416 under the Securities Act of 1933, as amended, this registration statement shall be deemed to cover any additional securities that may from time to time be offered or issued to prevent
dilution resulting from stock splits, reverse stock splits, stock dividends, recapitalizations or similar transactions.
(2)
Represents additional shares of Common Stock authorized for issuance under the 2013 Stock Incentive Plan.
(3)
Estimated solely for the purpose of calculating the registration fee pursuant to Rules 457(c) and 457(h) of the Securities Act of 1933, as amended. The price per share and aggregate offering price are calculated on the
basis of (i) $39.79, the weighted average exercise price of the 820,103 shares covered by this registration statement that are subject to outstanding stock option grants under the 2013 Stock Incentive Plan, at prices ranging from $35.20 to
$42.70, and (ii) $39.10, the average of the high and low prices of the Registrant's Common Stock as reported on the NASDAQ Global Market on March 2, 2015 with respect to the 412,129 shares covered by this registration statement
issuable under the 2013 Stock Incentive Plan that are not subject to outstanding awards.
Statement of Incorporation by Reference
This Registration Statement on Form S-8 is being filed to register the offer and sale of an additional 1,232,232 shares of Common Stock,
$0.001 par value per share, of Tetraphase Pharmaceuticals, Inc. (the "Registrant") authorized for issuance under the 2013 Stock Incentive Plan (the "2013 Plan") of the Registrant. Pursuant to General Instruction E to Form S-8,
except as otherwise set forth below, this Registration Statement incorporates by reference the contents of the Registration Statement on Form S-8 filed by the Registrant on June 14, 2013 (File No. 333- 189361) relating to the 2013 Plan.
PART II
INFORMATION REQUIRED IN THE REGISTRATION STATEMENT
Item 8. Exhibits.
The Index to Exhibits immediately preceding the exhibits is incorporated herein by reference.
- 1 -
SIGNATURES
Pursuant to the requirements of the Securities Act of 1933, the registrant 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 the city of Watertown, the Commonwealth of Massachusetts, on this 6
th
day of March, 2015.
TETRAPHASE PHARMACEUTICALS, INC.
By:
/s/ Guy Macdonald
Guy Macdonald
President and Chief Executive Officer
POWER OF ATTORNEY AND SIGNATURES
We, the undersigned officers and directors of Tetraphase Pharmaceuticals, Inc., hereby severally constitute and appoint Guy Macdonald and
David Lubner, and each of them singly, our true and lawful attorneys with full power to them, and each of them singly, to sign for us and in our names in the capacities indicated below, the registration statement on Form S-8 filed herewith and any
and all subsequent amendments to said registration statement, and generally to do all such things in our names and on our behalf in our capacities as officers and directors to enable Tetraphase Pharmaceuticals, Inc. to comply with the provisions of
the Securities Act of 1933, as amended, and all requirements of the Securities and Exchange Commission, hereby ratifying and confirming our signatures as they may be signed by our said attorneys, or any of them, to said registration statement and
any and all amendments thereto.
Pursuant to the requirements of the Securities Act of 1933, this registration statement has been signed
by the following persons in the capacities and on the dates indicated.
Signature
Title
Date
/s/ Guy Macdonald
President and Chief Executive Officer, Director (Principal Executive Officer)
March 6, 2015
Guy Macdonald
/s/ David C. Lubner
Senior Vice President and Chief Financial Officer (Principal Financial Officer and Principal Accounting Officer)
March 6, 2015
David C. Lubner
/s/ L. Patrick Gage
Director
March 6, 2015
L. Patrick Gage
/s/ Garen Bohlin
Director
March 6, 2015
Garen Bohlin
/s/ Jeffrey Chodakewitz
Director
March 6, 2015
Jeffrey Chodakewitz
/s/ John G. Freund
Director
March 6, 2015
John G. Freund
/s/ Steven R. Gullans
Director
March 6, 2015
Steven R. Gullans
/s/ Nancy Wysenski
Director
March 6, 2015
Nancy Wysenski
INDEX TO EXHIBITS
Number
Description
4.1(1)
Restated Certificate of Incorporation of the Registrant
4.2(1)
Amended and Restated Bylaws of the Registrant
5.1
Opinion of Wilmer Cutler Pickering Hale and Dorr LLP, counsel to the Registrant
23.1
Consent of Wilmer Cutler Pickering Hale and Dorr LLP
(included in Exhibit 5.1)
23.2
Consent of Ernst & Young LLP
24.1
Power of attorney (included on the signature pages of this registration statement)
99.1(2)
2013 Stock Incentive Plan
(1)
Incorporated by reference to the exhibit to the Registrant's quarterly report on Form 10-Q filed with the SEC on May 13, 2013.
(2)
Incorporated by reference to the Registrant's registration statement on Form S-1/A, filed with the Securities and Exchange Commission on March 5, 2013.