<SEC-DOCUMENT>0000078003-23-000079.txt : 20230710
<SEC-HEADER>0000078003-23-000079.hdr.sgml : 20230710
<ACCEPTANCE-DATETIME>20230710091042
ACCESSION NUMBER:		0000078003-23-000079
CONFORMED SUBMISSION TYPE:	SC 13G
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20230710
DATE AS OF CHANGE:		20230710

SUBJECT COMPANY:	

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Caribou Biosciences, Inc.
		CENTRAL INDEX KEY:			0001619856
		STANDARD INDUSTRIAL CLASSIFICATION:	BIOLOGICAL PRODUCTS (NO DIAGNOSTIC SUBSTANCES) [2836]
		IRS NUMBER:				453728228
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SC 13G
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	005-92726
		FILM NUMBER:		231078372

	BUSINESS ADDRESS:	
		STREET 1:		2929 7TH STREET, SUITE 105
		CITY:			BERKELEY
		STATE:			CA
		ZIP:			94710
		BUSINESS PHONE:		510-982-6030

	MAIL ADDRESS:	
		STREET 1:		2929 7TH STREET, SUITE 105
		CITY:			BERKELEY
		STATE:			CA
		ZIP:			94710

FILED BY:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			PFIZER INC
		CENTRAL INDEX KEY:			0000078003
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				135315170
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SC 13G

	BUSINESS ADDRESS:	
		STREET 1:		66 HUDSON BOULEVARD EAST
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10001-2192
		BUSINESS PHONE:		2127332323

	MAIL ADDRESS:	
		STREET 1:		66 HUDSON BOULEVARD EAST
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10001-2192

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	PFIZER CHARLES & CO INC
		DATE OF NAME CHANGE:	19710908
</SEC-HEADER>
<DOCUMENT>
<TYPE>SC 13G
<SEQUENCE>1
<FILENAME>caribou-13g_fv.htm
<DESCRIPTION>SC 13G CARIBOU BIOSCIENCES
<TEXT>
<html><head>
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<title>Document</title></head><body><div id="ie3ca14a305764978a3b480c479b14277_1"></div><div style="min-height:54pt;width:100%"><div style="text-align:right"><font><br></font></div></div><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:139%">&#160;</font></div><div style="margin-bottom:5pt;margin-top:5pt;text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:167%">UNITED STATES  <br>SECURITIES AND EXCHANGE COMMISSION  <br>WASHINGTON, D.C. 20549</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%"> </font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:167%">  <br> <br></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:167%">SCHEDULE 13G</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%"> </font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:167%">  <br></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:167%">UNDER THE SECURITIES EXCHANGE ACT OF 1934  </font></div><div style="margin-bottom:5pt;margin-top:5pt;text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:167%">(Amendment No.  _)*</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:167%"><br> <br></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:167%">CARIBOU BIOSCIENCES, INC.</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%"> <br>(Name of Issuer)</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:167%">  <br> <br></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:167%">Common Stock, par value $0.0001 per share</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%"> <br>(Title of Class of Securities)</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:167%">  <br> <br></font><font style="background-color:#ffffff;color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:167%">142038108</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:167%"><br></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%">(CUSIP Number)</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:167%">  <br> <br></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:167%">June 30, 2023</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%"><br>(Date of Event Which Requires Filing of this Statement)</font></div><div style="margin-bottom:5pt;margin-top:5pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">  <br></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">  Check the appropriate box to designate the rule pursuant to which this Schedule  <br>is filed&#58;</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">  <br></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">  <br>&#124;_&#124; Rule 13d-1(b)  <br>&#124;X&#124; Rule 13d-1(c)  <br>&#124;_&#124; Rule 13d-1(d)</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">  <br></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">  <br>*The remainder of this cover page shall be filled out for a reporting person's initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter disclosures provided in a prior cover page.</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">  <br></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">  <br>The information required on the remainder of this cover page shall not be deemed to be &#34;filed&#34; for the purpose of Section 18 of the Securities Exchange Act of 1934 (&#34;Act&#34;) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).</font></div><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:139%">&#160;</font></div><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:167%">&#160;</font></div><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:139%">&#160;</font></div><div><font><br></font></div><div style="height:54pt;position:relative;width:100%"><div style="bottom:0;position:absolute;width:100%"><div style="text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">Page </font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:100%">1</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%"> of </font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:100%">6</font></div><div><font><br></font></div></div></div><hr style="page-break-after:always"><div style="min-height:54pt;width:100%"><div style="padding-right:-4.5pt;text-align:right"><font><br></font></div></div><div><font><br></font></div><div style="margin-bottom:5pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:167%">CUSIP No. </font><font style="background-color:#ffffff;color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:167%">142038108</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:167%"><br></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:167%"> &#160;</font></div><div><table style="border-collapse:collapse;display:inline-table;margin-bottom:5pt;vertical-align:text-bottom;width:88.541%"><tr><td style="width:1.0%"></td><td style="width:5.958%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:14.866%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:3.942%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:70.834%"></td><td style="width:0.1%"></td></tr><tr style="height:14pt"><td colspan="12" style="padding:0 1pt"></td></tr><tr style="height:14pt"><td colspan="3" style="padding:0 1pt"></td><td colspan="9" style="border-bottom:1pt solid #000000;padding:0 1pt"></td></tr><tr><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt 2px 1.02pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">1.</font></td><td colspan="9" style="border-bottom:1pt solid #000000;border-right:1pt solid #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 1.02pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">Names of Reporting Persons. PFIZER INC.</font></td></tr><tr><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt 2px 1.02pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">2.</font></td><td colspan="9" style="border-bottom:1pt solid #000000;border-right:1pt solid #000000;border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="margin-bottom:1.5pt;margin-top:1.65pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">Check the Appropriate Box if a Member of a Group (See Instructions)  <br>(a)&#160;</font><font style="color:#000000;font-family:'Arial Unicode MS',sans-serif;font-size:12pt;font-weight:400;line-height:100%">&#9744;</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%"> <br>(b)&#160;</font><font style="color:#000000;font-family:'Arial Unicode MS',sans-serif;font-size:12pt;font-weight:400;line-height:100%">&#9744;</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%"> </font></div></td></tr><tr><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt 2px 1.02pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">3.</font></td><td colspan="9" style="border-bottom:1pt solid #000000;border-right:1pt solid #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 1.02pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">SEC Use Only</font></td></tr><tr><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt 2px 1.02pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">4.</font></td><td colspan="9" style="border-right:1pt solid #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 1.02pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">Citizenship or Place of Organization&#58; Delaware</font></td></tr><tr style="height:27pt"><td colspan="6" rowspan="4" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">NUMBER OF  <br>SHARES  <br>BENEFICIALLY  <br>OWNED BY EACH REPORTING  <br>PERSON WITH&#58;</font></div></td><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt 2px 1.02pt;text-align:left;vertical-align:middle"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">5.</font></td><td colspan="3" style="border-right:1pt solid #000000;border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">Sole Voting Power&#58; 4,690,431</font><font style="background-color:#ffffff;color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%"> shares of common stock, $0.0001 par value per share (&#8220;Common Stock&#8221;) </font><font style="background-color:#ffffff;color:#000000;font-family:'Times New Roman',sans-serif;font-size:7.8pt;font-weight:400;line-height:100%;position:relative;top:-4.2pt;vertical-align:baseline">(1)</font></div></td></tr><tr style="height:24pt"><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt 2px 1.02pt;text-align:left;vertical-align:middle"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">6.</font></td><td colspan="3" style="border-right:1pt solid #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 1.02pt;text-align:left;vertical-align:middle"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">Shared Voting Power&#58; -0-</font></td></tr><tr style="height:15pt"><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt 2px 1.02pt;text-align:left;vertical-align:middle"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">7.</font></td><td colspan="3" style="border-right:1pt solid #000000;border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">Sole Dispositive Power&#58; 4,690,431</font><font style="background-color:#ffffff;color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%"> shares of Common Stock</font></div></td></tr><tr style="height:27pt"><td colspan="3" style="border-bottom:1pt solid #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 1.02pt;text-align:left;vertical-align:middle"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">8.</font></td><td colspan="3" style="border-bottom:1pt solid #000000;border-right:1pt solid #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 1.02pt;text-align:left;vertical-align:middle"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">Shared Dispositive Power&#58; -0-</font></td></tr><tr><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt 2px 1.02pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">9.</font></td><td colspan="9" style="border-bottom:1pt solid #000000;border-right:1pt solid #000000;border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="margin-bottom:1.5pt;margin-top:1.65pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">Aggregate Amount Beneficially Owned by Reporting Person&#58; 4,690,431</font><font style="background-color:#ffffff;color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%"> shares of Common Stock</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%"> are beneficially owned by Pfizer Inc.</font></div></td></tr><tr><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt 2px 1.02pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">10.</font></td><td colspan="9" style="border-bottom:1pt solid #000000;border-right:1pt solid #000000;border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="margin-bottom:1.5pt;margin-top:1.65pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">Check if the Aggregate Amount in Row (9) Excludes Certain Shares  <br>(See Instructions) </font></div></td></tr><tr><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt 2px 1.02pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">11.</font></td><td colspan="9" style="border-bottom:1pt solid #000000;border-right:1pt solid #000000;border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="margin-bottom:1.5pt;margin-top:1.65pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:139%">Percent of Class Represented by Amount in Row (9)&#58; 7.1%</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7.8pt;font-weight:400;line-height:139%;position:relative;top:-4.2pt;vertical-align:baseline">(2)</font></div></td></tr><tr><td colspan="3" style="border-bottom:1pt solid #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 1.02pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">12.</font></td><td colspan="9" style="border-bottom:1pt solid #000000;border-right:1pt solid #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 1.02pt;text-align:left;vertical-align:top"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">Type of Reporting Person (See Instructions)&#58; CO</font></td></tr></table></div><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:139%">&#160;</font></div><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:167%">&#160;</font></div><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:139%">(1) On June 29, 2023, the issuer and the Reporting Person entered into a Voting Agreement, pursuant to which the Reporting Person agreed to cause such securities that are beneficially owned by it representing beneficial ownership of voting securities of the issuer in excess of 4.99% of the then issued and outstanding voting securities of the issuer to be voted (i) with respect to any matter directly relating to remuneration of directors, directors&#8217; insurance or indemnification or release from liability of directors, in a manner proportionally consistent with the votes properly cast for and against by holders of voting securities of the issuer not beneficially owned by the Reporting Person, and (ii) with respect to any other matter in which the Reporting Person shall have the right to vote such voting securities of the issuer, in accordance with the recommendation of the Board of Directors of the issuer or any applicable committee thereof.</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:139%"> </font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:139%">The term of the Voting Agreement is 12 months.</font></div><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:139%">(2)  &#160;Based on 66,054,144 shares of Common Stock outstanding, consisting of 4,690,431 shares of Common Stock issued to the Reporting Person pursuant to a Securities Purchase Agreement, dated June 29, 2023, by and between the issuer and the Reporting Person, and 61,363,713 shares of Common Stock outstanding as of May 4, 2023 reported in the issuer&#8217;s Quarterly Report on Form 10-Q for the quarterly period ended March 31, 2023 filed with the Securities and Exchange Commission on May 9, 2023.</font></div><div><font><br></font></div><div style="height:54pt;position:relative;width:100%"><div style="bottom:0;position:absolute;width:100%"><div style="text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">Page </font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:100%">2</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%"> of </font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:100%">6</font></div><div style="padding-right:-4.5pt;text-align:center"><font><br></font></div></div></div><hr style="page-break-after:always"><div style="min-height:54pt;width:100%"><div style="padding-right:-4.5pt;text-align:right"><font><br></font></div></div><div><font><br></font></div><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:139%">CUSIP No. </font><font style="background-color:#ffffff;color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:139%">142038108</font></div><div><font><br></font></div><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:167%">ITEM 1. </font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:167%"> <br></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%">(A) NAME OF ISSUER&#58;</font></div><div style="margin-top:5pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">Caribou Biosciences, Inc.</font></div><div style="margin-top:5pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%"><br>(B) ADDRESS OF ISSUER'S PRINCIPAL EXECUTIVE OFFICE&#58;  </font></div><div><font><br></font></div><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">2929 7th Street, Suite&#160;105, Berkeley, California 94710</font></div><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"><br></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%"> </font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> <br></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:100%">ITEM 2. </font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> <br></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">(A) NAME OF PERSON FILING&#58; </font></div><div style="margin-top:8pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%">Pfizer Inc. </font></div><div><font><br></font></div><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">(B) ADDRESS OR PRINCIPAL BUSINESS OFFICE OR IF NONE, RESIDENCE&#58; </font></div><div style="margin-top:5pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">66 Hudson Boulevard East, New York, NY 10001-2192 </font></div><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%"><br>(C) CITIZENSHIP&#58; </font></div><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%">Delaware, U.S.A. </font></div><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%"> <br>(D) TITLE OF CLASS OF SECURITIES&#58;</font></div><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%">Common stock, $0.0001 par value per share</font></div><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%"> <br>(E) CUSIP NUMBER&#58;</font></div><div><font style="background-color:#ffffff;color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%">142038108</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:167%"><br></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%"> </font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:167%"> <br></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:167%">ITEM 3. </font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%">If this statement is filed pursuant to &#167;&#167;240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a&#58; Not applicable.  <br>(a) &#160;</font><font style="color:#000000;font-family:'Arial Unicode MS',sans-serif;font-size:12pt;font-weight:400;line-height:167%">&#9744;</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%">  Broker or dealer registered under section 15 of the Act (15 U.S.C. 78os).  <br>(b) &#160;</font><font style="color:#000000;font-family:'Arial Unicode MS',sans-serif;font-size:12pt;font-weight:400;line-height:167%">&#9744;</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%">  Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c).  <br>(c) &#160;</font><font style="color:#000000;font-family:'Arial Unicode MS',sans-serif;font-size:12pt;font-weight:400;line-height:167%">&#9744;</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%">  Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c).  <br>(d) &#160;</font><font style="color:#000000;font-family:'Arial Unicode MS',sans-serif;font-size:12pt;font-weight:400;line-height:167%">&#9744;</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%">  Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8).</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:167%">  <br></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%">(e) &#160;</font><font style="color:#000000;font-family:'Arial Unicode MS',sans-serif;font-size:12pt;font-weight:400;line-height:167%">&#9744;</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%">  An investment adviser in accordance with &#167;240.13d-1(b)(1)(ii)(E).  <br>(f ) </font><font style="color:#000000;font-family:'Arial Unicode MS',sans-serif;font-size:12pt;font-weight:400;line-height:167%">&#9744;</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%">  An employee benefit plan or endowment fund in accordance with &#167;240.13d-1(b)(1)(ii)(F).  </font></div><div style="height:54pt;position:relative;width:100%"><div style="bottom:0;position:absolute;width:100%"><div style="text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">Page </font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:100%">3</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%"> of </font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:100%">6</font></div><div style="padding-right:-4.5pt;text-align:center"><font><br></font></div></div></div><hr style="page-break-after:always"><div style="min-height:54pt;width:100%"><div style="padding-right:-4.5pt;text-align:right"><font><br></font></div></div><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%"><br></font></div><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:167%">CUSIP No. </font><font style="background-color:#ffffff;color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:167%">142038108</font></div><div><font><br></font></div><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%">(g) &#160;</font><font style="color:#000000;font-family:'Arial Unicode MS',sans-serif;font-size:12pt;font-weight:400;line-height:167%">&#9744;</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%">  A parent holding company or control person in accordance with &#167;240.13d-1(b)(1)(ii)(G).  <br>(h) &#160;</font><font style="color:#000000;font-family:'Arial Unicode MS',sans-serif;font-size:12pt;font-weight:400;line-height:167%">&#9744;</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%">  A savings association as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813).  <br>(i)&#160;</font><font style="color:#000000;font-family:'Arial Unicode MS',sans-serif;font-size:12pt;font-weight:400;line-height:167%">&#9744;</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%"> A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3).  <br>(j) &#160;</font><font style="color:#000000;font-family:'Arial Unicode MS',sans-serif;font-size:12pt;font-weight:400;line-height:167%">&#9744;</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%">  A non-US institution, in accordance with &#167;240.13d-1(b)(1)(ii)(J)&#59;  <br>(k)&#160;</font><font style="color:#000000;font-family:'Arial Unicode MS',sans-serif;font-size:12pt;font-weight:400;line-height:167%">&#9744;</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%">  Group, in accordance with &#167;230.405 240.13d-1(b)(1)(ii)(K).</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:167%">  <br></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%">  <br>If filing as a non-US institution in accordance with &#167;240.13d-1(b)(1)(ii)(J), please specify the type of institution&#58; Not applicable. &#160;</font></div><div><font><br></font></div><div><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:167%">ITEM 4. OWNERSHIP. </font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:167%"> </font></div><div style="margin-bottom:5pt;margin-top:5pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%">See rows 5 through 11 of the cover page. </font></div><div style="margin-bottom:5pt;margin-top:5pt"><font><br></font></div><div style="margin-bottom:5pt;margin-top:5pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:167%">ITEM 5. OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS </font></div><div style="margin-bottom:5pt;margin-top:5pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%">Not applicable. &#160;</font></div><div style="margin-bottom:5pt;margin-top:5pt"><font><br></font></div><div style="margin-bottom:5pt;margin-top:5pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:167%">ITEM 6. OWNERSHIP OF MORE THAN FIVE PERCENT ON BEHALF OF ANOTHER PERSON </font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:167%"> <br></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%">Not applicable. &#160;</font></div><div style="margin-bottom:5pt;margin-top:5pt"><font><br></font></div><div style="margin-bottom:5pt;margin-top:5pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:167%">ITEM 7. IDENTIFICATION AND CLASSIFICATION OF THE SUBSIDIARY WHICH ACQUIRED THE SECURITY BEING REPORTED ON BY THE PARENT HOLDING COMPANY </font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%"> <br>Not applicable. &#160;</font></div><div style="margin-bottom:5pt;margin-top:5pt"><font><br></font></div><div style="margin-bottom:5pt;margin-top:5pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:167%">ITEM 8. IDENTIFICATION AND CLASSIFICATION OF MEMBERS OF THE GROUP </font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:167%"> <br></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%">Not applicable. &#160;</font></div><div style="height:54pt;position:relative;width:100%"><div style="bottom:0;position:absolute;width:100%"><div style="text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">Page </font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:100%">4</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%"> of </font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:100%">6</font></div><div style="padding-right:-4.5pt;text-align:center"><font><br></font></div></div></div><hr style="page-break-after:always"><div style="min-height:54pt;width:100%"><div style="padding-right:-4.5pt;text-align:right"><font><br></font></div></div><div style="margin-bottom:5pt;margin-top:5pt"><font><br></font></div><div style="margin-bottom:5pt;margin-top:5pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:167%">CUSIP No. </font><font style="background-color:#ffffff;color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:167%">142038108</font></div><div style="margin-bottom:5pt;margin-top:5pt"><font><br></font></div><div style="margin-bottom:5pt;margin-top:5pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:167%">ITEM 9. NOTICE OF DISSOLUTION OF GROUP </font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:167%"> <br></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%">Not applicable. &#160;</font></div><div style="margin-bottom:5pt;margin-top:5pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:167%">ITEM 10. CERTIFICATION</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:167%"> </font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:167%"> <br></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%">  <br>By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under &#167;240.14a-11.</font></div><div style="margin-bottom:5pt;margin-top:5pt"><font><br></font></div><div><font><br></font></div><div style="margin-bottom:5pt;margin-top:5pt;text-align:center"><font><br></font></div><div style="margin-bottom:5pt;margin-top:5pt;text-align:center"><font><br></font></div><div style="height:54pt;position:relative;width:100%"><div style="bottom:0;position:absolute;width:100%"><div style="text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">Page </font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:100%">5</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%"> of </font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:100%">6</font></div><div style="padding-right:-4.5pt;text-align:center"><font><br></font></div></div></div><hr style="page-break-after:always"><div style="min-height:54pt;width:100%"><div style="padding-right:-4.5pt;text-align:right"><font><br></font></div></div><div style="margin-bottom:5pt;text-align:center"><font><br></font></div><div style="margin-bottom:5pt;text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%">&#160;</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:167%">Signature</font></div><div style="margin-bottom:5pt;margin-top:5pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%">After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:167%">  <br> <br></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%">Dated&#58; July 10, 2023</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:167%"> <br> <br></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:167%">PFIZER INC.</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:167%">  <br></font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%">  <br>By&#58; &#47;s&#47; Susan Grant  <br>Name&#58; Susan Grant  <br>Title&#58; Assistant Secretary</font></div><div style="margin-bottom:5pt;margin-top:5pt"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:167%">&#160;</font></div><div style="height:54pt;position:relative;width:100%"><div style="bottom:0;position:absolute;width:100%"><div style="text-align:center"><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%">Page </font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:100%">6</font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:400;line-height:100%"> of </font><font style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:12pt;font-weight:700;line-height:100%">6</font></div><div style="padding-right:-4.5pt;text-align:center"><font><br></font></div></div></div></body></html>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
