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 W. HIGGINS ROAD, SUITE 1025 (Street) CHICAGO IL 60631 (City) (State) (Zip)	2. Date of Event Requiring Statement (Month/Day/Year) 07/15/2021	3. Issuer Name and Ticker or Trading Symbol Erasca, Inc. [ ERAS ]
		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 Preferred Stock	(1)	(1)	Common Stock	1,750,000	$0.00	I	By ARCH Venture Fund X, L.P.(2)(3)
Series A Preferred Stock	(1)	(1)	Common Stock	1,750,000	$0.00	I	By ARCH Venture Fund X Overage, L.P.(2)(3)
Series B-1 Preferred Stock	(4)	(4)	Common Stock	2,833,333	$0.00	I	By ARCH Venture Fund X, L.P.(2)(3)
Series B-2 Preferred Stock	(4)	(4)	Common Stock	944,444	$0.00	I	By ARCH Venture Fund X Overage, L.P.(2)(3)
Series B-1 Preferred Stock	(4)	(4)	Common Stock	2,833,333	$0.00	I	By ARCH Venture Fund X Overage, L.P.(2)
Series B-2 Preferred Stock	(4)	(4)	Common Stock	944,444	$0.00	I	By ARCH Venture Fund X Overage, L.P.(2)

1. Name and Address of Reporting Person* ARCH Venture Partners X, LLC (Last) (First) (Middle) 8755 W. HIGGINS ROAD, SUITE 1025 (Street) CHICAGO IL 60631 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* ARCH Venture Fund X, L.P. (Last) (First) (Middle) 8755 W. HIGGINS ROAD, SUITE 1025 (Street) CHICAGO IL 60631 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* ARCH Venture Fund X Overage, L.P. (Last) (First) (Middle) 8755 W. HIGGINS ROAD, SUITE 1025 (Street) CHICAGO IL 60631 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* ARCH Venture Partners X, L.P. (Last) (First) (Middle) 8755 W. HIGGINS ROAD, SUITE 1025 CHICAGO (Street) 60,631 IL (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* ARCH Venture Partners X Overage, L.P. (Last) (First) (Middle) 8755 W. HIGGINS ROAD, SUITE 1025 (Street) CHICAGO IL 60631 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* NELSEN ROBERT (Last) (First) (Middle) 8755 W. HIGGINS ROAD, SUITE 1025 (Street) CHICAGO IL 60631 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* CRANDELL KEITH (Last) (First) (Middle) 8755 W. HIGGINS ROAD, SUITE 1025 (Street) CHICAGO IL 60631 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

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) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* GILLIS STEVEN (Last) (First) (Middle) 8755 W. HIGGINS ROAD, SUITE 1025 (Street) CHICAGO IL 60631 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

Explanation of Responses:

1. The shares of Series A Preferred Stock are convertible, at any time, at the holder's election, to shares of the Issuer's common stock at a ratio of 1.2-for-1. In addition, effective immediately prior to the closing of the Issuer's initial public offering of its common stock, each share of Series A Preferred Stock will automatically convert to shares of the Issuer's common stock at a ratio of 1.2-for-1. The Series A Preferred Stock has no expiration date.

2. ARCH Venture Partners X, L.P. (AVP X LP) is the sole general partner of ARCH Venture Fund X, L.P. (ARCH X). ARCH Venture Partners X Overage, L.P. (AVP X Overage LP) is the sole general partner of ARCH Venture Fund X Overage, L.P. (ARCH X Overage). 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, Steven Gillis, and Robert Nelsen comprise 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.

3. (Continued from Footnote 2) AVP X LP, AVP X Overage LP, AVP X LLC, and the AVP X Committee Members each disclaim beneficial ownership except to any pecuniary interest therein.

4. The shares of Series B Preferred Stock are convertible, at any time, at the holder's election, to shares of the Issuer's common stock at a ratio of 1.2-for-1. In addition, effective immediately prior to the closing of the Issuer's initial public offering of its common stock, each share of Series B Preferred Stock will automatically convert to shares of the Issuer's common stock at a ratio of 1.2-for-1. The Series B Preferred Stock has no expiration date.

Remarks:

	/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	07/15/2021
	/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	07/15/2021
	/s/ ARCH Venture Partners X, L.P., its General Partner, By: ARCH Venture Partners X, LLC, its General Partner, By: Mark McDonnell, attorney-in-fact	07/15/2021
	/s/ 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	07/15/2021
	/s/ ARCH Venture Partners X, LLC, its General Partner, By: Mark McDonnell, attorney-in-fact	07/15/2021
	/s/ Robert Nelsen, By: Mark McDonnell, attorney-in-fact	07/15/2021
	/s/ Keith Crandell, By: Mark McDonnell, attorney-in-fact	07/15/2021
	/s/ Kristina Burow, By: Mark McDonnell, attorney-in-fact	07/15/2021
	/s/ Steven Gillis, By: Mark McDonnell, attorney-in-fact	07/15/2021
	** 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 5 (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).
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