Timothy Keutzer - 03 Feb 2025 Form 4 Insider Report for Spero Therapeutics, Inc. (SPRO)

Signature
/s/ Maegan Deare, Attorney-in-Fact for Timothy Keutzer
Issuer symbol
SPRO
Transactions as of
03 Feb 2025
Net transactions value
-$44,099
Form type
4
Filing time
05 Feb 2025, 21:04:51 UTC
Previous filing
29 Aug 2024
Next filing
03 Sep 2025

Transactions Table

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Ownership Footnotes
transaction SPRO Common Stock Award $0 +266,139 +50% $0.000000 797,976 03 Feb 2025 Direct F1
transaction SPRO Common Stock Sale $3,100 -3,974 -0.5% $0.7800 794,002 05 Feb 2025 Direct F2
transaction SPRO Common Stock Sale $21,562 -27,643 -3.5% $0.7800 766,359 05 Feb 2025 Direct F3
transaction SPRO Common Stock Sale $19,438 -24,920 -3.3% $0.7800 741,439 05 Feb 2025 Direct F4
* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id Content
F1 Consists of restricted stock units ("RSUs"). Each RSU represents the right to receive one share of common stock upon vesting. The RSUs vest in four equal annual installments beginning on February 3, 2026, subject to the Reporting Person's continued service through the applicable vesting date.
F2 The reported transaction is a sale of common stock effected to cover tax withholding obligations pursuant to a "sell to cover" provision included in each RSU Agreement in connection with the vesting of RSUs that were granted to the Reporting Person on February 1, 2022.
F3 The reported transaction is a sale of common stock effected to cover tax withholding obligations pursuant to a "sell to cover" provision included in each RSU Agreement in connection with the vesting of RSUs that were granted to the Reporting Person on February 1, 2023.
F4 The reported transaction is a sale of common stock effected to cover tax withholding obligations pursuant to a "sell to cover" provision included in each RSU Agreement in connection with the vesting of RSUs that were granted to the Reporting Person on February 1, 2024.