SHAFF ERIC D.

PrivateCIK: 1643734
Location

CAMBRIDGE, MA

SHAFF ERIC D. (See Remarks) sold 2.1% of their position (259.00 shares) of SERES THERAPEUTICS, INC. on the open market

Open‑market sale worth $2.0K — a minor trim. Review remaining holdings and any 10b5‑1 plan disclosures.

S · 1 sale
InsiderSHAFF ERIC D.CIK 1643734
IssuerSERES THERAPEUTICS, INC.CIK 1609809
Officer· See Remarks
Since Jan 2019
-259.00
Net shares
Net seller
$2.0K
Total sold
1
Open market trades
0B · 1S
4
Total transactions
722.00 acquired · 981.00 disposed
Non-Derivative Transactions2

Common Stock

Direct
M · Option Exercise

Shares

+722.00

Price / share

Trade value

% of position

6.2%
5/15/2026
11.58K12.30K

Common Stock

Direct
S · Sale

Shares

259.00

Price / share

$7.53

Trade value

$1.95K

% of position

2.1%
5/18/2026
12.30K12.04K
Total

Net shares

+463.00

Net value

-$1.95K

Derivative Transactions2

Restricted Stock Units

Direct
M · Option Exercise
Converts to

Common Stock

391.00 shares

Shares

391.00

Strike price

Held after

1.17K

Exercisable

5/15/2026

Restricted Stock Units

Direct
M · Option Exercise
Converts to

Common Stock

331.00 shares

Shares

331.00

Strike price

Held after

2.33K

Exercisable

5/15/2026
SHAFF ERIC D. — Insider Transaction (Form 4) Filed May 19, 2026 | Finecho