SEC Form 4

FORM 4		UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940	OMB APPROVAL OMB Number: 3235-0287 Estimated average burden hours per response: 0.5
	Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person* Casdin Eli (Last) (First) (Middle) C/O CORVEX MANAGEMENT LP 667 MADISON AVENUE (Street) NEW YORK NY 10065 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol Sema4 Holdings Corp. [ CMLF ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) X Director 10% Owner Officer (give title below) Other (specify below)
	3. Date of Earliest Transaction (Month/Day/Year) 07/22/2021
	4. If Amendment, Date of Original Filed (Month/Day/Year)	6. Individual or Joint/Group Filing (Check Applicable Line) X Form filed by One Reporting Person Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Class A Common Stock	07/22/2021		C(1)		10,993,750	A	$0	10,993,750	I	By CMLS Holdings LLC(2)
Class A Common Stock	07/22/2021		A		5,000,000	A	$0	5,000,000	I	Casdin Partners Master Fund, LP(3)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Warrants to purchase Class A Common Stock (right to buy)	$11.5	07/22/2021		A(4)		6,736,669		09/05/2021	09/05/2027(1)	Class A Common Stock	6,736,669	(4)	6,736,669	I	By CMLS Holdings LLC(2)
Class B Common Stock	(1)	07/22/2021		C(1)			10,993,750	(1)	(1)	Class A Common Stock	10,993,750	$0	0	I	By CMLS Holdings LLC(2)

Explanation of Responses:

1. In connection with the closing (the "Closing") of the business combination (the "Business Combination") between the Issuer (which was formerly known as CM Life Sciences, Inc. or "CMLS") and Mount Sinai Genomics, Inc. d/b/a Sema4 ("Sema4"), among other things, each share of CMLS's Class B common stock converted pursuant to the terms of such stock into shares of the Issuer's Class A Common Stock on a one-for-one basis.

2. The securities are held of record by CMLS Holdings LLC ("CMLS Holdings"). CMLS Holdings LLC is the record holder of the Class A common stock and the Class A Common Stock exercisable upon the issuance of warrants reported herein. The Board of Managers of CMLS Holdings LLC is comprised of Mr. Casdin and Mr. Keith Meister who share voting and investment discretion with respect to the Class A common stock held of record by CMLS Holdings LLC. C-LSH LLC and M-LSH LLC are the members of CMLS Holdings LLC, and Messrs. Casdin and Meister are the managing members of C-LSH LLC and M-LSH LLC, respectively. As such, Mr. Casdin may be deemed to have or share beneficial ownership of the securities held directly by CMLS Holdings LLC. Each of C-LSH LLC and Mr. Casdin disclaims beneficial ownership of these shares except to the extent of its or his respective pecuniary interest therein.

3. The securities reflected as beneficially owned by Casdin Partners Master Fund, LP in the table above consists of 5,000,000 shares of Class A common stock. Such securities are owned directly by Casdin Partners Master Fund, LP and may be deemed to be indirectly beneficially owned by (i) Casdin Capital, LLC, the investment adviser to Casdin Partners Master Fund, LP, (ii) Casdin Partners GP, LLC, the general partner of Casdin Partners Master Fund LP, and (iii) Mr. Casdin, the managing member of Casdin Capital, LLC and Casdin Partners GP, LLC. Each of Casdin Capital, LLC, Casdin Partners GP, LLC and Mr. Casdin disclaims beneficial ownership of such securities except to the extent of its or his respective pecuniary interest therein.

4. Following the completion of the business combination, warrants to purchase Class A Common Stock become exercisable on September 5, 2021, the date that is one year after the closing of the IPO of Sema4's predecessor, CMLS.

	/s/ Eli Casdin	07/26/2021
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.