SEC Form 4 · accession 0001193125-26-355722
Seres Therapeutics, Inc. · MCRB
Statement of changes in beneficial ownership, as filed. Original on EDGAR ↗
Reporting owner
Eric D. Shaff
Director
Period of report
Aug 15, 2026
Accepted (ET)
Aug 18, 2026 · 5:27 pm EDT
Rule 10b5-1 plan
yes — trade under a plan
Issuer CIK
0001609809
Table I — non-derivative securities
| Security | Date | Code | Shares | Price | A/D | Owned after | D/I | Nature of ownership |
|---|---|---|---|---|---|---|---|---|
| Common StockF1 | Aug 15, 2026 | M | 722 | — | A | 12,762 | D | |
| Common Stock | Aug 17, 2026 | S | 263 | $4.55 | D | 12,499 | D |
Table II — derivative securities
| Security | Conv. / exercise price | Date | Code | Shares | A/D | Exercisable | Expires | Underlying | Underlying shares | Owned after | D/I |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Restricted Stock UnitsF1,F3 | — | Aug 15, 2026 | M | 390 | D | — | — | Common Stock | 390 | 783 | D |
| Restricted Stock UnitsF1,F4 | — | Aug 15, 2026 | M | 332 | D | — | — | Common Stock | 332 | 1,993 | D |
Explanation of responses
- F1Each restricted stock unit represents a contingent right to receive one share of Issuer common stock.
- F2The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 instruction adopted by the reporting person on March 2, 2023, solely with the intent to cover taxes in connection with the vesting of the restricted stock units.
- F3The restricted stock units vested and settled as to 25% of the restricted stock units on February 15, 2024. The remainder of the restricted stock units have vested and settled or will vest and settle in 12 equal quarterly installments thereafter. The restricted stock units have no expiration date.
- F4The restricted stock units vested and settled as to 25% of the restricted stock units on February 15, 2025. The remainder of the restricted stock units have vested and settled or will vest and settle in 12 equal quarterly installments thereafter. The restricted stock units have no expiration date.