ARCH Venture Partners X, LLC - Jul 20, 2021 Form 4 Insider Report for Erasca, Inc. (ERAS)

Role: 10%+ Owner
Signature: /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
Stock symbol: ERAS
Transactions as of: Jul 20, 2021
Transactions value $: $0
Form type: 4
Date filed: 7/20/2021, 08:53 PM
Previous filing: Jul 15, 2021
Next filing: Oct 19, 2022

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	ERAS	Common Stock	Conversion of derivative security		+5.53M			5.53M	Jul 20, 2021	By ARCH Venture Fund X, L.P.	F1, F2, F3
transaction	ERAS	Common Stock	Conversion of derivative security		+5.53M			5.53M	Jul 20, 2021	By ARCH Venture Fund X Overage, L.P.	F1, F2, F3

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Underlying Class	Amount	Exercise Price	Ownership	Footnotes
transaction	ERAS	Series A Preferred Stock	Conversion of derivative security		-2.1M	-100%		0	Jul 20, 2021	Common Stock	1.75M	$0.00	By ARCH Venture Fund X, L.P.	F1, F2, F3
transaction	ERAS	Series A Preferred Stock	Conversion of derivative security		-2.1M	-100%		0	Jul 20, 2021	Common Stock	1.75M	$0.00	By ARCH Venture Fund X Overage, L.P.	F1, F2, F3
transaction	ERAS	Series B-1 Preferred Stock	Conversion of derivative security		-3.4M	-100%		0	Jul 20, 2021	Common Stock	2.83M	$0.00	By ARCH Venture Fund X, L.P.	F1, F2, F3
transaction	ERAS	Series B-2 Preferred Stock	Conversion of derivative security		-1.13M	-100%		0	Jul 20, 2021	Common Stock	944K	$0.00	By ARCH Venture Fund X, L.P.	F1, F2, F3
transaction	ERAS	Series B-1 Preferred Stock	Conversion of derivative security		-3.4M	-100%		0	Jul 20, 2021	Common Stock	2.83M	$0.00	By ARCH Venture Fund X Overage, L.P.	F1, F2, F3
transaction	ERAS	Series B-2 Preferred Stock	Conversion of derivative security		-1.13M	-100%		0	Jul 20, 2021	Common Stock	944K	$0.00	By ARCH Venture Fund X Overage, L.P.	F1, F2, F3

* An asterisk sign (*) next to the price indicates that the price is likely invalid.

ARCH Venture Partners X, LLC is no longer subject to Section 16 filing requirements. Form 4 or Form 5 obligations may continue.

Explanation of Responses:

Id	Content
F1	The shares of the Issuer's Series A and Series B Preferred Stock automatically converted into shares of the Issuer's Common Stock, for no additional consideration, at a ratio of 1.2-for-1 share, immediately prior to the consummation of the Issuer's initial public offering.
F2	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.
F3	(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.