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* Burow Kristina (Last) (First) (Middle) 8755 W. HIGGINS ROAD SUITE 1025 (Street) CHICAGO IL 60631 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol Beam Therapeutics Inc. [ BEAM ]	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) 02/10/2020
	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
Common Stock	02/10/2020		C(1)		4,121,520	A	(1)	4,121,520	I	See footnote(2)
Common Stock	02/10/2020		C(1)		4,121,519	A	(1)	4,121,519	I	See footnote(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
Series A-1 Preferred Stock	(1)	02/10/2020		C(1)			1,338,000	(1)	(1)	Common Stock	1,338,000	(1)	0	I	See footnote(2)
Series A-1 Preferred Stock	(1)	02/10/2020		C(1)			1,338,000	(1)	(1)	Common Stock	1,338,000	(1)	0	I	See footnote(3)
Series A-2 Preferred Stock	(1)	02/10/2020		C(1)			2,750,336	(1)	(1)	Common Stock	2,750,336	(1)	0	I	See footnote(2)
Series A-2 Preferred Stock	(1)	02/10/2020		C(1)			2,750,335	(1)	(1)	Common Stock	2,750,335	(1)	0	I	See footnote(3)
Series B Preferred Stock	(1)	02/10/2020		C(1)			33,184	(1)	(1)	Common Stock	33,184	(1)	0	I	See footnote(2)
Series B Preferred Stock	(1)	02/10/2020		C(1)			33,184	(1)	(1)	Common Stock	33,184	(1)	0	I	See footnote(3)

Explanation of Responses:

1. Upon closing of the Issuer's initial public offering, each share of Series A-1 Preferred Stock, Series A-2 Preferred Stock, and Series B Preferred Stock automatically converted into shares of Common Stock without payment or further consideration. There was no expiration date for the Series A-1 Preferred Stock, Series A-2 Preferred Stock, or Series B Preferred Stock.

2. The shares are held by ARCH Venture Fund IX, L.P. ("ARCH IX"). ARCH Venture Partners IX, L.P. ("GPLP"), as the sole general partner of ARCH IX, may be deemed to beneficially own the shares held by ARCH IX. ARCH Venture Partners IX, LLC ("GPLLC"), as the sole general partner of GPLP, may be deemed to beneficially own the shares held by GPLP. The Reporting Person has an interest in the GPLP and the GPLLC but does not have voting or investment control over the shares held by ARCH IX. The Reporting Person disclaims ownership of such shares, except to the extent of her pecuniary interest therein.

3. The shares are directly held by ARCH Venture Fund IX Overage, L.P. ("ARCH Overage"). ARCH Venture Partners IX Overage, L.P. ("Overage GPLP"), as the sole general partner of ARCH Overage, may be deemed to beneficially own the shares held by ARCH Overage. GPLLC, as the sole general partner of Overage GPLP, may be deemed to beneficially own the shares held by Overage GPLP. The Reporting Person has an interest in the Overage GPLP and the GPLLC but does not have voting or investment control over the shares held by ARCH Overage. The Reporting Person disclaims ownership of such shares, except to the extent of her pecuniary interest therein.

Remarks:

	By: Christine Bellon, Attorney-in-fact	02/11/2020
	** 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).
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