Kelly M. Brady - 02 Mar 2026 Form 3 Insider Report for Seres Therapeutics, Inc. (MCRB)

Role
EVP and Chief Operating Officer Exhibit 24 - Power of Attorney.
Signature
/s/ Thomas J. DesRosier, Attorney-in-Fact for Kelly M. Brady
Issuer symbol
MCRB
Transactions as of
02 Mar 2026
Net transactions value
$0
Form type
3
Filing time
11 Mar 2026, 18:30:43 UTC
Next filing
11 Mar 2026
SEC
View on sec.gov

Reporting Owners (1)

Name Relationship Address Signature Signature date CIK
Brady Kelly EVP and Chief Operating Officer Exhibit 24 - Power of Attorney. C/O SERES THERAPEUTICS, INC., 101 CAMBRIDGE PARK DRIVE, CAMBRIDGE /s/ Thomas J. DesRosier, Attorney-in-Fact for Kelly M. Brady 11 Mar 2026 0002117686

Transactions Table

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Ownership Footnotes
holding MCRB Common Stock 8,441 02 Mar 2026 Direct

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
holding MCRB Stock Option (right to buy) 02 Mar 2026 Common Stock 2,925 $22.00 Direct F1
holding MCRB Stock Option (right to buy) 02 Mar 2026 Common Stock 11,700 $15.64 Direct F2
holding MCRB Stock Option (right to buy) 02 Mar 2026 Common Stock 2,000 $23.00 Direct F3
holding MCRB Stock Option (right to buy) 02 Mar 2026 Common Stock 869 $23.00 Direct F3
holding MCRB Stock Option (right to buy) 02 Mar 2026 Common Stock 812 $23.00 Direct F3
holding MCRB Stock Option (right to buy) 02 Mar 2026 Common Stock 2,343 $23.00 Direct F3
holding MCRB Stock Option (right to buy) 02 Mar 2026 Common Stock 1,430 $23.00 Direct F4
holding MCRB Restricted Stock Units 02 Mar 2026 Common Stock 358 $0.000000 Direct F5
holding MCRB Restricted Stock Units 02 Mar 2026 Common Stock 730 $0.000000 Direct F6
* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id Content
F1 The options were granted on February 14, 2024. The option vested as to 25% of the shares on February 14, 2025. The remainder of the shares will vest in 12 equal quarterly installments thereafter.
F2 The options were granted on February 7, 2025. The option vested as to 25% of the shares on February 7, 2026. The remainder of the shares will vest in 12 equal quarterly installments thereafter.
F3 The stock options are fully vested.
F4 The options were granted on February 12, 2024. The option vested as to 25% of the shares on February 3, 2024. The remainder of the shares will vest in 12 equal quarterly installments thereafter.
F5 The restricted stock units were granted on February 3, 2023. The restricted stock units vested as to 25% of the shares on February 15, 2024. The remainder of the shares will vest in 12 equal quarterly installments thereafter. The restricted stock units have no expiration date.
F6 The restricted stock units were granted on February 14, 2024. The restricted stock units vested as to 25% of the shares on February 15, 2025. The remainder of the shares will vest in 12 equal quarterly installments thereafter. The restricted stock units have no expiration date.

Remarks:

EVP and Chief Operating Officer Exhibit 24 - Power of Attorney.