Exhibit 4.1


 


	NUMBER	UNITS
	U-	 
	 	 
	SEE REVERSE FOR CERTAIN DEFINITIONS	 
	 	 
	 	CUSIP           


 


CM LIFE SCIENCES III INC.


 


UNITS CONSISTING OF ONE SHARE OF CLASS
A COMMON STOCK AND ONE-FIFTH OF ONE REDEEMABLE WARRANT, EACH WHOLE WARRANT ENTITLING THE HOLDER TO PURCHASE ONE SHARE OF CLASS
A COMMON STOCK


 


THIS CERTIFIES THAT
                    is the owner of
                    Units.


 


Each Unit
(“Unit”) consists of one share of Class A common stock, par value $0.0001 per share
(“Common Stock”), of CM Life Sciences III Inc., a Delaware corporation (the
“Company”), and one-fifth of one redeemable warrant (the “Warrant”). Each
whole Warrant entitles the holder to purchase one share of Common Stock for $11.50 per share (subject to adjustment). Only
whole Warrants are exercisable. Each whole Warrant will become exercisable on the later of (i) thirty (30) days after the
Company’s completion of a merger, capital stock exchange, asset acquisition, stock purchase, reorganization or other
similar business combination with one or more businesses (each a “Business Combination”), and (ii)
twelve (12) months from the closing of the Company’s initial public offering, and will expire unless exercised before
5:00 p.m., New York City Time, on the date that is five (5) years after the date on which the Company completes its initial
Business Combination, or earlier upon redemption or liquidation (the “Expiration Date”). The Common
Stock and Warrants comprising the Units represented by this certificate are not transferable separately prior to
             , 2021, unless Jefferies LLC and Cowen and
Company, LLC elects to allow separate trading earlier, subject to the Company’s filing of a Current Report on Form 8-K
with the Securities and Exchange Commission containing an audited balance sheet reflecting the Company’s receipt of the
gross proceeds of the Company’s initial public offering and issuing a press release announcing when separate trading
will begin. No fractional Warrants will be issued upon separation of the Units. The terms of the Warrants are governed by a
Warrant Agreement, dated as of              , 2021, between
the Company and Continental Stock Transfer & Trust Company, as Warrant Agent, and are subject to the terms and provisions
contained therein, all of which terms and provisions the holder of this certificate consents to by acceptance hereof. Copies
of the Warrant Agreement are on file at the office of the Warrant Agent at 1 State Street, 30th Floor, New York,
New York 10004, and are available to any Warrant holder on written request and without cost.


 


This certificate is not valid unless countersigned
by the Transfer Agent and registered by the Registrar of the Company.


 


This certificate shall be governed by and
construed in accordance with the internal laws of the State of New York.


 


Witness the facsimile signature of a duly
authorized signatory of the Company.


 


	         _____________________________________
	_____________________________________
	Authorized Signatory	Transfer Agent






 






     


     


    





CM LIFE SCIENCES III INC.


 


The Company will furnish without charge
to each unitholder who so requests, a statement of the powers, designations, preferences and relative, participating, optional
or other special rights of each class of equity or series thereof of the Company and the qualifications, limitations, or restrictions
of such preferences and/or rights.


 


The following abbreviations, when used
in the inscription on the face of this certificate, shall be construed as though they were written out in full according to applicable
laws or regulations:


 


	
         

        TEN COM— as tenants in common

        TEN ENT— as tenants by the entireties

        JT TEN— as joint tenants
        with right of survivorship and not as tenants in common
	UNIF GIFT MIN ACT	
          Custodian 

        (Cust)(Minor)

        under Uniform Gifts to Minors Act

        ______________________________

        (State)



 


 


Additional abbreviations may also be
used though not in the above list.


 


For value received,                    hereby
sell, assign and transfer unto





(PLEASE INSERT SOCIAL
SECURITY OR OTHER DENTIFYING NUMBER OF ASSIGNEE)



(PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS, INCLUDING ZIP CODE, OF ASSIGNEE)


 


Units represented by the within Certificate,
and do hereby irrevocably constitute and appoint


 


Attorney to transfer the said Units on the
books of the within named Company with full power of substitution in the premises.


 





	Dated	_______________________________________________
	 	Notice: The signature to this assignment
must correspond with the name as written upon the face of the certificate in every particular, without alteration or enlargement
or any change whatever.


 




    2


     


    


 


Signature(s) Guaranteed:


 





	_______________________________________________	
	THE SIGNATURE(S) MUST BE GUARANTEED BY AN ELIGIBLE
GUARANTOR INSTITUTION (BANKS, STOCKBROKERS, SAVINGS AND LOAN ASSOCIATIONS AND CREDIT UNIONS WITH MEMBERSHIP IN AN APPROVED SIGNATURE
GUARANTEE MEDALLION PROGRAM, PURSUANT TO S.E.C. RULE 17Ad-15 UNDER THE SECURITIES EXCHANGE ACT OF 1934, AS AMENDED (OR ANY SUCCESSOR
RULE)).	


 


As more fully described in, and subject to the terms and conditions
described in, the Company’s final prospectus for its initial public offering dated              , 2021, the holder(s) of this certificate
shall be entitled to receive a pro rata portion of certain funds held in the trust account established in connection with the Company’s
initial public offering only in the event that (i) the Company redeems the shares of Common Stock sold in the Company’s initial
public offering and liquidates because it does not consummate an initial business combination by the date set forth (the “Last
Date”) in the Company’s Amended and Restated Certificate of Incorporation, as the same may be amended from time to
time (the “Charter”), (ii) the Company redeems the shares of Common Stock sold in its initial public offering properly
submitted in connection with a stockholder vote to amend the Charter to modify the substance or timing of the Company’s obligation
to redeem 100% of the Common Stock if it does not consummate an initial business combination by the Last Date or with respect to
any other material provisions relating to stockholders’ rights or pre-initial business combination activity, or (iii) if
the holder(s) seek(s) to redeem for cash his, her or its respective shares of Common Stock in connection with a tender offer (or
proxy solicitation, solely in the event the Company seeks stockholder approval of the proposed initial business combination) setting
forth the details of a proposed initial business combination. In no other circumstances shall the holder(s) have any right or interest
of any kind in or to the trust account.





 


 


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