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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&nbsp;11, 2024 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="right"><B>Registration <FONT STYLE="white-space:nowrap">No.&nbsp;333-&#8195;&#8195;&#8195;&#8195;</FONT> </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 <FONT
STYLE="white-space:nowrap">S-8</FONT></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>Caribou Biosciences, 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">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center"><B><FONT STYLE="white-space:nowrap">45-3728228</FONT></B></TD></TR>
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<TD VALIGN="top" ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(State or other jurisdiction of</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>incorporation or organization)</B></P></TD>
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<TD VALIGN="top" ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(I.R.S. Employer</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Identification Number)</B></P></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>2929 7th Street, Suite 105</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Berkeley, CA</B></P></TD>
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<TD VALIGN="bottom" ALIGN="center"><B>94710</B></TD></TR>
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<TD VALIGN="top" ALIGN="center"><B>(Address of Principal Executive Offices)</B></TD>
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<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>Caribou Biosciences, Inc. 2021 Equity Incentive Plan </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Caribou Biosciences, Inc. 2021 Employee Stock Purchase 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>Rachel E. Haurwitz, Ph.D. </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>Caribou Biosciences, Inc. </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>2929 7th Street, Suite 105 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Berkeley, California 94710 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>(510) <FONT STYLE="white-space:nowrap">982-6030</FONT></B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(Name, address, including zip code, and telephone number, including area code, of agent for service) </B></P>
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<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B><I>Copies to: </I></B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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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>Ashok W. Mukhey, Esq.</B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Reed Smith LLP</B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>1901
Avenue of the Stars, Suite 700</B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Los Angeles, California 90067</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Telephone: (310) <FONT STYLE="white-space:nowrap">734-5200</FONT></B></P></TD>
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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>Barbara G. McClung, Esq.</B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Caribou Biosciences, Inc.</B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>2929 7th Street, Suite 105</B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Berkeley, California 94710</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Telephone: (510) <FONT STYLE="white-space:nowrap">982-6030</FONT></B></P></TD>
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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>Jeffrey G. Aromatorio, Esq.</B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Reed Smith LLP</B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>225 Fifth
Avenue</B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Pittsburgh, Pennsylvania 15222</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Telephone: (412) <FONT STYLE="white-space:nowrap">288-3364</FONT></B></P></TD></TR>
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<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 <FONT STYLE="white-space:nowrap">non-accelerated</FONT>
filer, a smaller reporting company or an emerging growth company. See the definitions of &#147;large accelerated filer,&#148; &#147;accelerated filer,&#148; &#147;smaller reporting company&#148; and &#147;emerging growth company&#148; in Rule <FONT
STYLE="white-space:nowrap">12b-2</FONT> 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"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman">Large&nbsp;accelerated&nbsp;filer</P></TD>
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<TD VALIGN="bottom"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman">&#9744;</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman">Accelerated&nbsp;filer</P></TD>
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<TD VALIGN="bottom"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman">&#9744;</P></TD></TR>
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<TD VALIGN="bottom"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman"><FONT STYLE="white-space:nowrap">Non-accelerated&nbsp;filer</FONT></P></TD>
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<TD VALIGN="bottom"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman">&#9746;</P></TD>
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<TD VALIGN="bottom"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman">Smaller&nbsp;reporting&nbsp;company</P></TD>
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<TD VALIGN="bottom"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman">&#9746;</P></TD></TR>
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<TD VALIGN="bottom"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman">Emerging&nbsp;growth&nbsp;company</P></TD>
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<TD VALIGN="bottom"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman">&#9746;</P></TD></TR>
</TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period
for complying with any new or revised financial accounting standards provided pursuant to Section&nbsp;7(a)(2)(B) of the Securities Act.&#8194;&#9744; </P> <P STYLE="font-size:10pt;margin-top:0pt;margin-bottom:0pt">&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>EXPLANATORY NOTE </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 <FONT STYLE="white-space:nowrap">S-8</FONT> is filed by Caribou Biosciences, Inc., a Delaware corporation
(the &#147;Registrant&#148;), relating to 4,422,447 shares of its common stock, par value $0.0001 per share (the &#147;Common Stock&#148;), to be issued pursuant to the Registrant&#146;s 2021 Equity Incentive Plan (&#147;2021 EIP&#148;) and 884,489
shares of Common Stock to be issued pursuant to the Registrant&#146;s 2021 Employee Stock Purchase Plan (&#147;2021 ESPP&#148;), which Common Stock is in addition to the 12,829,421 shares of Common Stock already issuable under the 2021 EIP and the
1,723,922 shares of Common Stock already issuable under the 2021 ESPP as registered on the Registrant&#146;s Form <FONT STYLE="white-space:nowrap">S-8</FONT> filed with the Securities and Exchange Commission (the &#147;Commission&#148;) on
July&nbsp;26, 2021 (<A HREF="http://www.sec.gov/Archives/edgar/data/1619856/000119312521224325/d178219ds8.htm"><U>File No.</U><U></U><U><FONT STYLE="white-space:nowrap">&nbsp;333-258173</FONT></U></A>), Form
<FONT STYLE="white-space:nowrap">S-8</FONT> filed with the Commission on March&nbsp;
21, 2022 (<A HREF="http://www.sec.gov/Archives/edgar/data/1619856/000156459022011219/ck1619856-s8.htm"><U>File No.</U><U></U><U><FONT STYLE="white-space:nowrap">&nbsp;333-263750</FONT></U></A>), and Form <FONT STYLE="white-space:nowrap">S-8</FONT>
filed with the Commission on March&nbsp;9, 2023 (<A HREF="http://www.sec.gov/Archives/edgar/data/1619856/000119312523066300/d467633ds8.htm">File No.<U></U><FONT STYLE="white-space:nowrap">&nbsp;333-270431</FONT></A>) (collectively, the &#147;Prior
Registration Statements&#148;). These additional shares of Common Stock have been reserved for issuance as a result of the operation of the &#147;evergreen&#148; provisions in the Registrant&#146;s 2021 EIP and 2021 ESPP, which provide that the
total number of shares subject to such plans may be increased each year pursuant to a specified formula. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">This Registration Statement
relates to securities of the same class as that to which the Prior Registration Statements relate, and is submitted in accordance with General Instruction E to Form <FONT STYLE="white-space:nowrap">S-8</FONT> regarding Registration of Additional
Securities. Pursuant to General Instruction E of Form <FONT STYLE="white-space:nowrap">S-8,</FONT> the contents of the Prior Registration Statements are incorporated herein by reference and made part of this Registration Statement, except as amended
hereby. </P> <P STYLE="margin-top:24pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>PART I </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 SECTION 10(a) PROSPECTUS </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The information called for in Part I of Form <FONT STYLE="white-space:nowrap">S-8</FONT> is not being filed with or included in this Form <FONT
STYLE="white-space:nowrap">S-8</FONT> (by incorporation by reference or otherwise) in accordance with the rules and regulations of the Securities and Exchange Commission (the &#147;Commission&#148;). </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; font-size:10pt; font-family:Times New Roman"><I>In this registration statement, Caribou Biosciences, Inc. is sometimes referred to as
&#147;Registrant,&#148; &#147;we,&#148; &#147;us,&#148; or &#147;our.&#148; </I></P> <P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Item&#8201;3. Incorporation of Documents by Reference. </B></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The following documents previously filed by Caribou Biosciences, Inc. (the &#147;Registrant&#148;) with the Commission are incorporated by reference into this
Registration Statement: </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD VALIGN="top">(a)</TD>
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<TD VALIGN="top">Registrant&#146;s Annual Report on <A HREF="http://www.sec.gov/Archives/edgar/data/../../../ix?doc=/Archives/edgar/data/1619856/000161985624000013/crbu-20231231.htm">Form <FONT STYLE="white-space:nowrap">10-K</FONT></A> for the year
ended December&nbsp;31, 2023 filed with the Commission on March&nbsp;11, 2024;</TD></TR>
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<TD VALIGN="top">(b)</TD>
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<TD VALIGN="top">Registrant&#146;s Current Reports on <A HREF="http://www.sec.gov/Archives/edgar/data/1619856/000161985624000003/crbu-20240107.htm"><FONT STYLE="white-space:nowrap">Form&nbsp;8-K</FONT></A> filed on&nbsp;January&nbsp;8, 2024 (except
Item 7.01); and</TD></TR>
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<TD VALIGN="top">(c)</TD>
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<TD VALIGN="top">The description of the Registrant&#146;s Common Stock which is contained in a registration statement on <A HREF="http://www.sec.gov/Archives/edgar/data/1619856/000119312521218592/d128937d8a12b.htm">Form <FONT
STYLE="white-space:nowrap">8-A</FONT></A> filed on July&nbsp;19, 2021 (File <FONT STYLE="white-space:nowrap">No.&nbsp;001-40631)</FONT> under the Securities Exchange Act of 1934, as amended (the &#147;Exchange Act&#148;), as updated by the
description of the Registrant&#146;s capital stock contained in Exhibit 4.1 to the Registrant&#146;s Annual Report on Form <FONT STYLE="white-space:nowrap">10-K,</FONT> for the fiscal year ended December&nbsp;31, 2021, including any amendment or
report filed for the purpose of updating such description.</TD></TR>
</TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">All documents that the Registrant subsequently files pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act prior
to the filing of a post-effective amendment to this registration statement which indicates that all of the shares of common stock offered have been sold or which deregisters all of such shares then remaining unsold, shall be deemed to be
incorporated by reference into this registration statement and to be a part hereof from the date of the filing of such documents; except as to any portion of any future annual or quarterly report to stockholders or document or current report
</P>
</DIV></Center>


<p style="margin-top:1em; margin-bottom:0em; page-break-before:always"> </p>
<HR SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">


<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">
furnished under current Items 2.02 or 7.01 of Form <FONT STYLE="white-space:nowrap">8-K,</FONT> and exhibits furnished on such form that relate to such items, that is not deemed filed under such
provisions. For the purposes of this registration statement, any statement contained in a document incorporated or deemed to be incorporated by reference herein shall be deemed to be modified or superseded to the extent that a statement contained
herein or in any other subsequently filed document which also is or is deemed to be incorporated by reference herein 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. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Under no circumstances will any information filed under current Items 2.02 or 7.01 of
Form <FONT STYLE="white-space:nowrap">8-K,</FONT> and exhibits furnished on such form that relate to such items, be deemed incorporated herein by reference unless such Form <FONT STYLE="white-space:nowrap">8-K</FONT> expressly provides to the
contrary. </P> <P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Item&#8201;8. Exhibits. </B></P> <P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Reference is made
under this Item 8 to the exhibit index included in this Registration Statement. </P>
</DIV></Center>


<p style="margin-top:1em; margin-bottom:0em; page-break-before:always"> </p>
<HR SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">


<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Exhibit Index </B></P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" ALIGN="center">


<TR>

<TD></TD>

<TD VALIGN="bottom" WIDTH="5%"></TD>
<TD WIDTH="92%"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:8pt">
<TD VALIGN="bottom" ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Exhibit</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Number</B></P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Exhibit Description</B></P></TD></TR>


<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>4.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/1619856/000119312521227378/d189230dex31.htm">Amended and Restated Certificate of Incorporation, as currently in effect (incorporated herein by reference to Exhibit 3.1 to the Registrant&#146;s
 Current Report on Form <FONT STYLE="white-space:nowrap">8-K</FONT> (File <FONT STYLE="white-space:nowrap">No.&nbsp;001-40631),</FONT> filed with the Commission on July&nbsp;28, 2021). </A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>4.2</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/1619856/000119312521227378/d189230dex32.htm">Amended and Restated Bylaws, as currently in effect (incorporated herein by reference to Exhibit 3.2 to the Registrant&#146;s Current Report on
 Form <FONT STYLE="white-space:nowrap">8-K</FONT> (File <FONT STYLE="white-space:nowrap">No.&nbsp;001-40631),</FONT> filed with the Commission on July&nbsp;28, 2021). </A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>5.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="d787569dex51.htm">Opinion of Reed Smith LLP. </A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>23.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="d787569dex231.htm">Consent of Independent Registered Public Accounting Firm. </A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>23.2</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="d787569dex51.htm">Consent of Reed Smith LLP (reference is made to Exhibit 5.1). </A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>24.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="#sig">Power of Attorney (reference is made to the signature page hereto). </A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>99.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/1619856/000119312521224325/d178219dex996.htm">2021 Equity Incentive Plan (incorporated herein by reference to Exhibit 99.6 to the Registrant&#146;s Registration Statement on Form <FONT
STYLE="white-space:nowrap">S-8</FONT> (File <FONT STYLE="white-space:nowrap">No.&nbsp;333-258173),</FONT> filed with the Commission on July&nbsp;26, 2021). </A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>99.2</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/1619856/000095017022004233/crbu-ex10_50.htm">Form of Employee Stock Option Agreement under the 2021 Equity Incentive Plan of the Registrant (incorporated herein by reference to Exhibit 10.50
to the Registrant&#146;s Annual Current Report on Form <FONT STYLE="white-space:nowrap">10-K</FONT> (File <FONT STYLE="white-space:nowrap">No.&nbsp;001-40631)</FONT> for the period ended December&nbsp;31, 2021, filed with the Commission on
March&nbsp;21, 2022). </A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>99.3</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/1619856/000095017022004233/crbu-ex10_51.htm">Form of <FONT STYLE="white-space:nowrap">Non-Employee</FONT> Director Stock Option Agreement under the 2021 Equity Incentive Plan of the Registrant
 (incorporated herein by reference to Exhibit 10.51 to the Registrant&#146;s Annual Report on Form <FONT STYLE="white-space:nowrap">10-K</FONT> (File <FONT STYLE="white-space:nowrap">No.&nbsp;001-40631)</FONT> for the period ended December&nbsp;31,
2021, filed with the Commission on March&nbsp;21, 2022). </A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>99.4</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/1619856/000095017022004233/crbu-ex10_52.htm">Form of Restricted Stock Unit Award Grant Notice and Restricted Stock Unit Award Agreement under the 2021 Equity Incentive Plan of the Registrant
 (incorporated herein by reference to Exhibit 10.52 to the Registrant&#146;s Annual Report on Form <FONT STYLE="white-space:nowrap">10-K</FONT> (File <FONT STYLE="white-space:nowrap">No.&nbsp;001-40631)</FONT> for the period ended December&nbsp;31,
2021, filed with the Commission on March&nbsp;21, 2022). </A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>99.5</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/1619856/000161985622000022/exhibit101-rsuagreement.htm">Form of Restricted Stock Unit Award Grant Notice and Restricted Stock Unit Award Agreement under the 2021 Equity Incentive Plan of
 the Registrant (incorporated by reference to Exhibit 10.1 of the Registrant&#146;s Quarterly Report on Form <FONT STYLE="white-space:nowrap">10-Q</FONT> (File <FONT STYLE="white-space:nowrap">No.&nbsp;001-40631)</FONT> for the period ended
September&nbsp;30, 2022, filed with the Commission on November&nbsp;8, 2022). </A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>99.6</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/1619856/000161985622000022/exhibit102-psuagreement.htm">Form of Performance Stock Unit Award Grant Notice and Performance Stock Unit Award Agreement under the 2021 Equity Incentive Plan of
 the Registrant (incorporated herein by reference to Exhibit 10.2 to the Registrant&#146;s Quarterly Report on Form <FONT STYLE="white-space:nowrap">10-Q</FONT> (File <FONT STYLE="white-space:nowrap">No.&nbsp;001-40631)</FONT> for the period ended
September&nbsp;30, 2022, filed with the Commission on November&nbsp;8, 2022). </A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>99.7</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/1619856/000119312521224325/d178219dex997.htm">2021 Employee Stock Purchase Plan (incorporated herein by reference to Exhibit 99.7 to the Registrant&#146;s Registration Statement on Form
<FONT STYLE="white-space:nowrap">S-8</FONT> (File <FONT STYLE="white-space:nowrap">No.&nbsp;333-258173),</FONT> filed with the Commission on July&nbsp;26, 2021). </A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>107</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="d787569dexfilingfees.htm">Filing Fee Table </A></TD></TR>
</TABLE>
</DIV></Center>


<p style="margin-top:1em; margin-bottom:0em; page-break-before:always"> </p>
<HR SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">


<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B><A NAME="sig"></A>SIGNATURES </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; 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 <FONT STYLE="white-space:nowrap">S-8</FONT> and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Berkeley, State of California, on
this 11th day of March, 2024. </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="40%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt">


<TR>

<TD WIDTH="7%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="92%"></TD></TR>


<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" COLSPAN="3"><B>Caribou Biosciences, Inc.</B></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">By:</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Rachel E. Haurwitz</P></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Rachel E. Haurwitz</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"><I>President and Chief Executive Officer</I></TD></TR>
</TABLE> <P STYLE="margin-top:24pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>POWER OF ATTORNEY </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below does hereby constitute and appoint Rachel E. Haurwitz, Barbara G. McClung,
and Jason V. O&#146;Byrne and each of them, with full power of substitution and full power to act without the other, his or her true and lawful <FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">attorney-in-fact</FONT></FONT> and
agent to act for him or her in his or her name, place and stead, in any and all capacities, to sign any and all amendments (including post-effective amendments) to this registration statement, and to file this registration statement, with all
exhibits thereto, and other documents in connection therewith, with the SEC, granting unto said <FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">attorneys-in-fact</FONT></FONT> and agents, and each of them, full power and authority
to do and perform each and every act and thing requisite and necessary to be done in order to effectuate the same as fully, to all intents and purposes, as they or he or she might or could do in person, hereby ratifying and confirming all that said <FONT
STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">attorneys-in-fact</FONT></FONT> and agents, or any of them, may lawfully do or cause to be done by virtue hereof. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; 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
date indicated. </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt">


<TR>

<TD WIDTH="38%"></TD>

<TD VALIGN="bottom"></TD>
<TD WIDTH="44%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="16%"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:8pt">
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Signature</B></P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Title</B></P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Date</B></P></TD></TR>


<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman" ALIGN="center">/s/ Rachel E. Haurwitz</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Rachel E. Haurwitz</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">President and Chief Executive Officer and Director</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman"><I>(Principal Executive Officer)</I></P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center">March&nbsp;11, 2024</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="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman" ALIGN="center">/s/ Jason V. O&#146;Byrne</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Jason V. O&#146;Byrne</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Chief Financial Officer</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><I>(Principal Financial
Officer and Principal</I></P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman"><I>Accounting Officer)</I></P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center">March&nbsp;11, 2024</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="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman" ALIGN="center">/s/ Scott Braunstein</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Scott Braunstein</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Director</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center">March&nbsp;11, 2024</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="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman" ALIGN="center">/s/ Andrew Guggenhime</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Andrew Guggenhime</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Director</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center">March&nbsp;11, 2024</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="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman" ALIGN="center">/s/ David Johnson</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">David Johnson</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Director</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center">March&nbsp;11, 2024</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="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman" ALIGN="center">/s/ Dara Richardson-Heron</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Dara Richardson-Heron</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Director</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center">March&nbsp;11, 2024</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="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman" ALIGN="center">/s/ Natalie Sacks</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Natalie Sacks</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Director</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center">March&nbsp;11, 2024</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="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman" ALIGN="center">/s/ Nancy Whiting</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Nancy Whiting</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Director</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center">March&nbsp;11, 2024</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="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman" ALIGN="center">/s/ Ran Zheng</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Ran Zheng</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Director</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center">March&nbsp;11, 2024</TD></TR>
</TABLE>
</DIV></Center>

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{"company-data": {"conformed-name": "Caribou Biosciences, Inc.", "cik": "0001619856", "assigned-sic": "2836", "organization-name": "03 Life Sciences", "irs-number": "453728228", "state-of-incorporation": "DE", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-277827", "film-number": "24739031"}, "business-address": {"street1": "2929 7TH STREET, SUITE 105", "city": "BERKELEY", "state": "CA", "zip": "94710", "phone": "510-982-6030"}, "mail-address": {"street1": "2929 7TH STREET, SUITE 105", "city": "BERKELEY", "state": "CA", "zip": "94710"}}
S-8
As filed with the Securities and Exchange Commission on March 11, 2024
Registration
No. 333-
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM
S-8
REGISTRATION STATEMENT
UNDER
THE
SECURITIES ACT OF 1933
Caribou Biosciences, Inc.
(Exact name of Registrant as specified in its charter)
Delaware
45-3728228
(State or other jurisdiction of
incorporation or organization)
(I.R.S. Employer
Identification Number)
2929 7th Street, Suite 105
Berkeley, CA
94710
(Address of Principal Executive Offices)
(Zip Code)
Caribou Biosciences, Inc. 2021 Equity Incentive Plan
Caribou Biosciences, Inc. 2021 Employee Stock Purchase Plan
(Full Title of the Plan)
Rachel E. Haurwitz, Ph.D.
President and Chief Executive Officer
Caribou Biosciences, Inc.
2929 7th Street, Suite 105
Berkeley, California 94710
(510)
982-6030
(Name, address, including zip code, and telephone number, including area code, of agent for service)
Copies to:
Ashok W. Mukhey, Esq.
Reed Smith LLP
1901
Avenue of the Stars, Suite 700
Los Angeles, California 90067
Telephone: (310)
734-5200
Barbara G. McClung, Esq.
Caribou Biosciences, Inc.
2929 7th Street, Suite 105
Berkeley, California 94710
Telephone: (510)
982-6030
Jeffrey G. Aromatorio, Esq.
Reed Smith LLP
225 Fifth
Avenue
Pittsburgh, Pennsylvania 15222
Telephone: (412)
288-3364
Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a
non-accelerated
filer, a smaller reporting company or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company" and "emerging growth company" in Rule
12b-2
of the Exchange Act.
Large accelerated filer
☐
Accelerated filer
☐
Non-accelerated filer
☒
Smaller reporting company
☒
Emerging growth company
☒
If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period
for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. ☐
EXPLANATORY NOTE
This Registration Statement on Form
S-8
is filed by Caribou Biosciences, Inc., a Delaware corporation
(the "Registrant"), relating to 4,422,447 shares of its common stock, par value $0.0001 per share (the "Common Stock"), to be issued pursuant to the Registrant's 2021 Equity Incentive Plan ("2021 EIP") and 884,489
shares of Common Stock to be issued pursuant to the Registrant's 2021 Employee Stock Purchase Plan ("2021 ESPP"), which Common Stock is in addition to the 12,829,421 shares of Common Stock already issuable under the 2021 EIP and the
1,723,922 shares of Common Stock already issuable under the 2021 ESPP as registered on the Registrant's Form
S-8
filed with the Securities and Exchange Commission (the "Commission") on
July 26, 2021 (
File No.
333-258173
), Form
S-8
filed with the Commission on March 
21, 2022 (
File No.
333-263750
), and Form
S-8
filed with the Commission on March 9, 2023 (
File No.
333-270431
) (collectively, the "Prior
Registration Statements"). These additional shares of Common Stock have been reserved for issuance as a result of the operation of the "evergreen" provisions in the Registrant's 2021 EIP and 2021 ESPP, which provide that the
total number of shares subject to such plans may be increased each year pursuant to a specified formula.
This Registration Statement
relates to securities of the same class as that to which the Prior Registration Statements relate, and is submitted in accordance with General Instruction E to Form
S-8
regarding Registration of Additional
Securities. Pursuant to General Instruction E of Form
S-8,
the contents of the Prior Registration Statements are incorporated herein by reference and made part of this Registration Statement, except as amended
hereby.
PART I
INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS
The information called for in Part I of Form
S-8
is not being filed with or included in this Form
S-8
(by incorporation by reference or otherwise) in accordance with the rules and regulations of the Securities and Exchange Commission (the "Commission").
PART II
INFORMATION
REQUIRED IN THE REGISTRATION STATEMENT
In this registration statement, Caribou Biosciences, Inc. is sometimes referred to as
"Registrant," "we," "us," or "our."
Item 3. Incorporation of Documents by Reference.
The following documents previously filed by Caribou Biosciences, Inc. (the "Registrant") with the Commission are incorporated by reference into this
Registration Statement:
(a)
Registrant's Annual Report on
Form
10-K
for the year
ended December 31, 2023 filed with the Commission on March 11, 2024;
(b)
Registrant's Current Reports on
Form 8-K
filed on January 8, 2024 (except
Item 7.01); and
(c)
The description of the Registrant's Common Stock which is contained in a registration statement on
Form
8-A
filed on July 19, 2021 (File
No. 001-40631)
under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), as updated by the
description of the Registrant's capital stock contained in Exhibit 4.1 to the Registrant's Annual Report on Form
10-K,
for the fiscal year ended December 31, 2021, including any amendment or
report filed for the purpose of updating such description.
All documents that the Registrant subsequently files pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act prior
to the filing of a post-effective amendment to this registration statement which indicates that all of the shares of common stock offered have been sold or which deregisters all of such shares then remaining unsold, shall be deemed to be
incorporated by reference into this registration statement and to be a part hereof from the date of the filing of such documents; except as to any portion of any future annual or quarterly report to stockholders or document or current report
furnished under current Items 2.02 or 7.01 of Form
8-K,
and exhibits furnished on such form that relate to such items, that is not deemed filed under such
provisions. For the purposes of this registration statement, any statement contained in a document incorporated or deemed to be incorporated by reference herein shall be deemed to be modified or superseded to the extent that a statement contained
herein or in any other subsequently filed document which also is or is deemed to be incorporated by reference herein 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.
Under no circumstances will any information filed under current Items 2.02 or 7.01 of
Form
8-K,
and exhibits furnished on such form that relate to such items, be deemed incorporated herein by reference unless such Form
8-K
expressly provides to the
contrary.
Item 8. Exhibits.
Reference is made
under this Item 8 to the exhibit index included in this Registration Statement.
Exhibit Index
Exhibit
Number
Exhibit Description
4.1
Amended and Restated Certificate of Incorporation, as currently in effect (incorporated herein by reference to Exhibit 3.1 to the Registrant's
 Current Report on Form
8-K
(File
No. 001-40631),
filed with the Commission on July 28, 2021).
4.2
Amended and Restated Bylaws, as currently in effect (incorporated herein by reference to Exhibit 3.2 to the Registrant's Current Report on
 Form
8-K
(File
No. 001-40631),
filed with the Commission on July 28, 2021).
5.1
Opinion of Reed Smith LLP.
23.1
Consent of Independent Registered Public Accounting Firm.
23.2
Consent of Reed Smith LLP (reference is made to Exhibit 5.1).
24.1
Power of Attorney (reference is made to the signature page hereto).
99.1
2021 Equity Incentive Plan (incorporated herein by reference to Exhibit 99.6 to the Registrant's Registration Statement on Form
S-8
(File
No. 333-258173),
filed with the Commission on July 26, 2021).
99.2
Form of Employee Stock Option Agreement under the 2021 Equity Incentive Plan of the Registrant (incorporated herein by reference to Exhibit 10.50
to the Registrant's Annual Current Report on Form
10-K
(File
No. 001-40631)
for the period ended December 31, 2021, filed with the Commission on
March 21, 2022).
99.3
Form of
Non-Employee
Director Stock Option Agreement under the 2021 Equity Incentive Plan of the Registrant
 (incorporated herein by reference to Exhibit 10.51 to the Registrant's Annual Report on Form
10-K
(File
No. 001-40631)
for the period ended December 31,
2021, filed with the Commission on March 21, 2022).
99.4
Form of Restricted Stock Unit Award Grant Notice and Restricted Stock Unit Award Agreement under the 2021 Equity Incentive Plan of the Registrant
 (incorporated herein by reference to Exhibit 10.52 to the Registrant's Annual Report on Form
10-K
(File
No. 001-40631)
for the period ended December 31,
2021, filed with the Commission on March 21, 2022).
99.5
Form of Restricted Stock Unit Award Grant Notice and Restricted Stock Unit Award Agreement under the 2021 Equity Incentive Plan of
 the Registrant (incorporated by reference to Exhibit 10.1 of the Registrant's Quarterly Report on Form
10-Q
(File
No. 001-40631)
for the period ended
September 30, 2022, filed with the Commission on November 8, 2022).
99.6
Form of Performance Stock Unit Award Grant Notice and Performance Stock Unit Award Agreement under the 2021 Equity Incentive Plan of
 the Registrant (incorporated herein by reference to Exhibit 10.2 to the Registrant's Quarterly Report on Form
10-Q
(File
No. 001-40631)
for the period ended
September 30, 2022, filed with the Commission on November 8, 2022).
99.7
2021 Employee Stock Purchase Plan (incorporated herein by reference to Exhibit 99.7 to the Registrant's Registration Statement on Form
S-8
(File
No. 333-258173),
filed with the Commission on July 26, 2021).
107
Filing Fee Table
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 Berkeley, State of California, on
this 11th day of March, 2024.
Caribou Biosciences, Inc.
By:
/s/ Rachel E. Haurwitz
Rachel E. Haurwitz
President and Chief Executive Officer
POWER OF ATTORNEY
KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below does hereby constitute and appoint Rachel E. Haurwitz, Barbara G. McClung,
and Jason V. O'Byrne and each of them, with full power of substitution and full power to act without the other, his or her true and lawful
attorney-in-fact
and
agent to act for him or her in his or her name, place and stead, in any and all capacities, to sign any and all amendments (including post-effective amendments) to this registration statement, and to file this registration statement, with all
exhibits thereto, and other documents in connection therewith, with the SEC, granting unto said
attorneys-in-fact
and agents, and each of them, full power and authority
to do and perform each and every act and thing requisite and necessary to be done in order to effectuate the same as fully, to all intents and purposes, as they or he or she might or could do in person, hereby ratifying and confirming all that said
attorneys-in-fact
and agents, or any of them, may lawfully do or cause to be done by virtue hereof.
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
date indicated.
Signature
Title
Date
/s/ Rachel E. Haurwitz
Rachel E. Haurwitz
President and Chief Executive Officer and Director
(Principal Executive Officer)
March 11, 2024
/s/ Jason V. O'Byrne
Jason V. O'Byrne
Chief Financial Officer
(Principal Financial
Officer and Principal
Accounting Officer)
March 11, 2024
/s/ Scott Braunstein
Scott Braunstein
Director
March 11, 2024
/s/ Andrew Guggenhime
Andrew Guggenhime
Director
March 11, 2024
/s/ David Johnson
David Johnson
Director
March 11, 2024
/s/ Dara Richardson-Heron
Dara Richardson-Heron
Director
March 11, 2024
/s/ Natalie Sacks
Natalie Sacks
Director
March 11, 2024
/s/ Nancy Whiting
Nancy Whiting
Director
March 11, 2024
/s/ Ran Zheng
Ran Zheng
Director
March 11, 2024