Jean Francois Formela - Aug 17, 2021 Form 4 Insider Report for Spero Therapeutics, Inc. (SPRO)

Role: Director
Signature: /s/ Matthew J. Gardella, as Attorney-in-Fact for Jean Francois Formela
Stock symbol: SPRO
Transactions as of: Aug 17, 2021
Transactions value $: $0
Form type: 4
Date filed: 8/18/2021, 04:41 PM
Previous filing: Jun 29, 2021
Next filing: Sep 14, 2021

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	SPRO	Stock Option (right to buy)	Award	$0	+7.5K		$0.00	7.5K	Aug 17, 2021	Common Stock	7.5K	$13.69	Direct	F1, F2

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

Explanation of Responses:

Id	Content
F1	The shares underlying this option will vest and become exercisable in full on August 17, 2022 subject to the Reporting Person's continued service as a director through the vesting date.
F2	The reporting person is a member of Atlas Venture Associates IX, LLC and is obligated to transfer the economic benefit, if any, received upon the sale of the shares issuable upon exercise of the equity grants to Atlas Venture Advisors, L.P. As such, the Reporting Person disclaims beneficial ownership to the securities reported herein for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, except to the extent of his pecuniary interest therein, if any.

Content

The shares underlying this option will vest and become exercisable in full on August 17, 2022 subject to the Reporting Person's continued service as a director through the vesting date.

The reporting person is a member of Atlas Venture Associates IX, LLC and is obligated to transfer the economic benefit, if any, received upon the sale of the shares issuable upon exercise of the equity grants to Atlas Venture Advisors, L.P. As such, the Reporting Person disclaims beneficial ownership to the securities reported herein for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, except to the extent of his pecuniary interest therein, if any.