Crandell Keith Form 3 Prime Medicine / KEITH CRANDELL ownership change

SEC Form 3

FORM 3

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person^*

ARCH Venture Partners X, LLC

(Last) (First) (Middle)

8755 WEST HIGGINS ROAD, SUITE 1025

(Street)

CHICAGO IL 60631

(City) (State) (Zip)

2. Date of Event Requiring Statement (Month/Day/Year)
10/19/2022

3. Issuer Name and Ticker or Trading Symbol
Prime Medicine, Inc. [ PRME ]

4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

Director	X	10% Owner
Officer (give title below)		Other (specify below)

5. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

	Form filed by One Reporting Person
X	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Beneficially Owned
1. Title of Security (Instr. 4)	2. Amount of Securities Beneficially Owned (Instr. 4)	3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	4. Nature of Indirect Beneficial Ownership (Instr. 5)

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Series A Convertible Preferred Stock	(1)	(1)	Common Stock	5,361,122	(1)	I	By ARCH Venture Fund X, L.P(2)(3)
Series A Convertible Preferred Stock	(1)	(1)	Common Stock	5,361,122	(1)	I	By ARCH Venture Fund X Overage, L.P.(2)(4)
Series B Convertible Preferred Stock	(1)	(1)	Common Stock	367,175	(1)	I	By ARCH Venture Fund X, L.P.(2)(3)
Series B Convertible Preferred Stock	(1)	(1)	Common Stock	367,175	(1)	I	By ARCH Venture Fund X Overage, L.P.(2)(4)

1. Name and Address of Reporting Person^*

ARCH Venture Partners X, LLC

(Last) (First) (Middle)

8755 WEST HIGGINS ROAD, SUITE 1025

(Street)

CHICAGO IL 60631

(City) (State) (Zip)

1. Name and Address of Reporting Person^*

ARCH Venture Partners X, L.P.

(Last) (First) (Middle)

8755 WEST HIGGINS ROAD, SUITE 1025

(Street)

CHICAGO IL 60631

(City) (State) (Zip)

1. Name and Address of Reporting Person^*

ARCH Venture Partners X Overage, L.P.

(Last) (First) (Middle)

8755 WEST HIGGINS ROAD, SUITE 1025

(Street)

CHICAGO IL 60631

(City) (State) (Zip)

1. Name and Address of Reporting Person^*

ARCH Venture Fund X, L.P.

(Last) (First) (Middle)

8755 WEST HIGGINS ROAD, SUITE 1025

(Street)

CHICAGO IL 60631

(City) (State) (Zip)

1. Name and Address of Reporting Person^*

ARCH Venture Fund X Overage, L.P.

(Last) (First) (Middle)

8755 WEST HIGGINS ROAD, SUITE 1025

(Street)

CHICAGO IL 60631

(City) (State) (Zip)

1. Name and Address of Reporting Person^*

CRANDELL KEITH

(Last) (First) (Middle)

8755 WEST HIGGINS ROAD, SUITE 1025

(Street)

CHICAGO IL 60631

(City) (State) (Zip)

1. Name and Address of Reporting Person^*

Burow Kristina

(Last) (First) (Middle)

8755 WEST HIGGINS ROAD, SUITE 1025

(Street)

CHICAGO IL 60631

(City) (State) (Zip)

1. Name and Address of Reporting Person^*

GILLIS STEVEN

(Last) (First) (Middle)

8755 WEST HIGGINS ROAD, SUITE 1025

(Street)

CHICAGO IL 60631

(City) (State) (Zip)

Explanation of Responses:

1. The shares of Series A Convertible Preferred Stock and Series B Convertible Preferred Stock (together, the "Preferred Stock") are convertible into Common Stock on a one-for-3.10880 basis at any time at the option of the holder, and will automatically convert into the number of shares shown in Column 3 immediately prior to the closing of the Issuer's initial public offering. The Preferred Stock has no expiration date.

2. ARCH Venture Partners X, LLC ("AVP X LLC") is the sole general partner of each of AVP X LP and AVP X Overage LP. Keith Crandell, Kristina Burow and Steven Gillis are members of the investment committee of AVP X LLC (the "AVP X Committee Members"). AVP X LP and AVP X Overage LP may be deemed to beneficially own the shares held by ARCH X and ARCH X Overage, respectively, AVP X LLC may be deemed to beneficially own the shares held by ARCH X and ARCH X Overage, and each of the AVP X Committee Members may be deemed to share the power to direct the disposition and vote of the shares held by ARCH X and ARCH X Overage. AVP X LP, AVP X Overage LP, AVP X LLC, and the AVP X Committee Members each disclaim beneficial ownership except to the extent of any pecuniary interest therein, and this report shall not be deemed an admission that such shares are beneficially owned by them for Section 16 or any other purpose.

3. Represents shares held directly by ARCH Venture Fund X, L.P. ("ARCH X"). ARCH Venture Partners X, L.P. ("AVP X LP") is the sole general partner of ARCH X.

4. Represents shares held directly by ARCH Venture Fund X Overage, L.P. ("ARCH X Overage"). ARCH Venture Partners X Overage, L.P. ("AVP X Overage LP") is the sole general partner of ARCH X Overage.

Remarks:

Exhibit 24 Power of Attorney. Exhibit 24.1 Power of Attorney

	/s/ ARCH Venture Fund X, L.P., By: ARCH Venture Partners X, L.P., its General Partner, By: ARCH Venture Partners X, LLC, its General Partner, By: Mark McDonnell, attorney-in-fact	10/19/2022
	/s/ ARCH Venture Fund X Overage, L.P., By: ARCH Venture Partners X Overage, L.P., its General Partner, By: ARCH Venture Partners X, LLC, its General Partner, By: Mark McDonnell, attorney-in-fact	10/19/2022
	/s/ ARCH Venture Partners X, L.P., By: ARCH Venture Partners X, LLC, its General Partner, By: Mark McDonnell, attorney-in-fact	10/19/2022
	/s/ ARCH Venture Partners X Overage, L.P., By: ARCH Venture Partners X, LLC, its General Partner, By: Mark McDonnell, attorney-in-fact	10/19/2022
	/s/ ARCH Venture Partners X, LLC, By: Mark McDonnell, attorney-in-fact	10/19/2022
	/s/ Keith Crandell, By: Mark McDonnell, attorney-in-fact	10/19/2022
	/s/ Kristina Burow, By: Mark McDonnell, attorney-in-fact	10/19/2022
	/s/ Steven Gillis, By: Mark McDonnell, attorney-in-fact	10/19/2022
	** Signature of Reporting Person	Date
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