DESROSIER THOMAS

PrivateCIK: 1435744
Location

LEXINGTON, MA

DESROSIER THOMAS (See Remarks) sold 1.0% of their position (79.00 shares) of SERES THERAPEUTICS, INC. on the open market

Open‑market sale worth $594.87 — a minor trim. Review remaining holdings and any 10b5‑1 plan disclosures.

S · 1 sale
InsiderDESROSIER THOMASCIK 1435744
IssuerSERES THERAPEUTICS, INC.CIK 1609809
Officer· See Remarks
Since Mar 2026
-79.00
Net shares
Net seller
$594.87
Total sold
1
Open market trades
0B · 1S
4
Total transactions
244.00 acquired · 323.00 disposed
Non-Derivative Transactions2

Common Stock

Direct
M · Option Exercise

Shares

+244.00

Price / share

Trade value

% of position

3.1%
5/15/2026
7.79K8.03K

Common Stock

Direct
S · Sale

Shares

79.00

Price / share

$7.53

Trade value

$594.87

% of position

1.0%
5/18/2026
8.03K7.95K
Total

Net shares

+165.00

Net value

-$594.87

Derivative Transactions2

Restricted Stock Units

Direct
M · Option Exercise
Converts to

Common Stock

133.00 shares

Shares

133.00

Strike price

Held after

398.00

Exercisable

5/15/2026

Restricted Stock Units

Direct
M · Option Exercise
Converts to

Common Stock

111.00 shares

Shares

111.00

Strike price

Held after

779.00

Exercisable

5/15/2026
DESROSIER THOMAS — Insider Transaction (Form 4) Filed May 19, 2026 | Finecho