Mina Kim - May 9, 2023 Form 4 Insider Report for ACELYRIN, Inc. (SLRN)

Role: Chief Legal & Admin. Officer
Signature: /s/ Mina Kim
Stock symbol: SLRN
Transactions as of: May 9, 2023
Transactions value $: $90,000
Form type: 4
Date filed: 5/11/2023, 08:58 PM
Previous filing: May 4, 2023
Next filing: Aug 18, 2023

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	SLRN	Common Stock	Purchase	$90K	+5K		$18.00	5K	May 9, 2023	Direct	F1

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	SLRN	Employee Stock Option (right to buy)	Other	$0	-363K	-100%	$0.00^*	0	May 9, 2023	Class A Common Stock	363K	$5.88	Direct	F2, F3
transaction	SLRN	Employee Stock Option (right to buy)	Other	$0	+363K		$0.00	363K	May 9, 2023	Common Stock	363K	$5.88	Direct	F2, F3
transaction	SLRN	Employee Stock Option (right to buy)	Other	$0	-85.2K	-100%	$0.00^*	0	May 9, 2023	Class A Common Stock	85.2K	$18.00	Direct	F2, F4
transaction	SLRN	Employee Stock Option (right to buy)	Other	$0	+85.2K		$0.00	85.2K	May 9, 2023	Common Stock	85.2K	$18.00	Direct	F2, F4

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

Explanation of Responses:

Id	Content
F1	Reflects shares purchased through a directed share program in the Issuer's initial public offering of Common Stock (the "IPO").
F2	Each share of Class A Common Stock was reclassified into one share of Common Stock immediately prior to the completion of the IPO.
F3	1/4 of the shares subject to the option vest on November 14, 2023, and 1/48 of the shares subject to the option vests in equal monthly installments thereafter, subject to the Reporting Person's continued service.
F4	1/4 of the shares subject to the option vest on May 4, 2024, and 1/48 of the shares subject to the option vest in equal monthly installments thereafter, subject to the Reporting Person's continued service.