Thomas DesRosier

CIK: 0001435744

Transaction Breakdown

Open Market Buys (P)0 (0.0%)

High conviction signal

Open Market Sales (S)9 (36.0%)

Position reduction

Option Exercises (M)13 (52.0%)

Derivative conversions

Awards (A)3 (12.0%)

Compensation grants

Other (G, F, J, C, D, …)0 (0.0%)

Gifts, tax withholding, conversions, dispositions to the issuer and other codes

Companies & Roles (1)

MCRB

Seres Therapeutics, Inc.

Officer

Discretionary Trading P&L

Holdings

Transaction History (25 total)

MCRB
Seres Therapeutics, Inc.
Aug 17, 2026
Sale(S)
Direct
82 shares at avg. $4.55$373.1
MCRB
Seres Therapeutics, Inc.
Aug 15, 2026
Exercise(M)
Direct
245 shares-
MCRB
Seres Therapeutics, Inc.
Jul 8, 2026
Award(A)
Stock Option (right to buy)
Direct
7.5K shares-
MCRB
Seres Therapeutics, Inc.
May 18, 2026
Sale(S)
Direct
79 shares at avg. $7.53$594.87
MCRB
Seres Therapeutics, Inc.
May 15, 2026
Exercise(M)
Direct
244 shares-
MCRB
Seres Therapeutics, Inc.
Mar 4, 2026
Award(A)
Stock Option (right to buy)
Direct
22.5K shares-
MCRB
Seres Therapeutics, Inc.
Feb 15, 2026
Sale(S)
Direct
78 shares at avg. $8.47$660.66
MCRB
Seres Therapeutics, Inc.
Feb 15, 2026
Exercise(M)
Direct
244 shares-
MCRB
Seres Therapeutics, Inc.
Nov 15, 2025
Exercise(M)
Direct
112 shares-
MCRB
Seres Therapeutics, Inc.
Nov 15, 2025
Exercise(M)
Direct
132 shares-
MCRB
Seres Therapeutics, Inc.
Nov 15, 2025
Sale(S)
Direct
76 shares at avg. $17.30$1K
MCRB
Seres Therapeutics, Inc.
Aug 18, 2025
Sale(S)
Direct
76 shares at avg. $16.65$1K
MCRB
Seres Therapeutics, Inc.
Aug 15, 2025
Exercise(M)
Direct
133 shares-
MCRB
Seres Therapeutics, Inc.
Aug 15, 2025
Exercise(M)
Direct
111 shares-
MCRB
Seres Therapeutics, Inc.
May 15, 2025
Exercise(M)
Direct
133 shares-
MCRB
Seres Therapeutics, Inc.
May 15, 2025
Sale(S)
Direct
79 shares at avg. $7.28$575.12
MCRB
Seres Therapeutics, Inc.
May 15, 2025
Exercise(M)
Direct
111 shares-
MCRB
Seres Therapeutics, Inc.
Feb 18, 2025
Sale(S)
Direct
4.3K shares at avg. $0.81$3K
MCRB
Seres Therapeutics, Inc.
Feb 15, 2025
Exercise(M)
Direct
2.7K shares-
MCRB
Seres Therapeutics, Inc.
Feb 15, 2025
Exercise(M)
Direct
8.9K shares-
MCRB
Seres Therapeutics, Inc.
Feb 7, 2025
Award(A)
Stock Option (Right to Buy)
Direct
650K shares-
MCRB
Seres Therapeutics, Inc.
Nov 18, 2024
Sale(S)
Direct
878 shares at avg. $0.54$474.735
MCRB
Seres Therapeutics, Inc.
Nov 15, 2024
Exercise(M)
Direct
2.7K shares-
MCRB
Seres Therapeutics, Inc.
Oct 28, 2024
Sale(S)
Direct
4.3K shares at avg. $0.69$3K
MCRB
Seres Therapeutics, Inc.
Oct 27, 2024
Exercise(M)
Direct
13.5K shares-

		Type	Shares	Price		Ownership
Aug 17, 2026	MCRB Seres Therapeutics, Inc.	Sale(S)	82	$4.55	$373	Direct
Aug 15, 2026	MCRB Seres Therapeutics, Inc.	Exercise(M)	245	-	$0	Direct
Jul 8, 2026	MCRB Seres Therapeutics, Inc.	Award(A) Stock Option (right to buy)	7,500	-	-	Direct
May 18, 2026	MCRB Seres Therapeutics, Inc.	Sale(S)	79	$7.53	$595	Direct
May 15, 2026	MCRB Seres Therapeutics, Inc.	Exercise(M)	244	-	$0	Direct
Mar 4, 2026	MCRB Seres Therapeutics, Inc.	Award(A) Stock Option (right to buy)	22,500	-	-	Direct
Feb 15, 2026	MCRB Seres Therapeutics, Inc.	Sale(S)	78	$8.47	$661	Direct
Feb 15, 2026	MCRB Seres Therapeutics, Inc.	Exercise(M)	244	-	$0	Direct
Nov 15, 2025	MCRB Seres Therapeutics, Inc.	Exercise(M)	112	-	-	Direct
Nov 15, 2025	MCRB Seres Therapeutics, Inc.	Exercise(M)	132	-	-	Direct
Nov 15, 2025	MCRB Seres Therapeutics, Inc.	Sale(S)	76	$17.30	$1,315	Direct
Aug 18, 2025	MCRB Seres Therapeutics, Inc.	Sale(S)	76	$16.65	$1,265	Direct
Aug 15, 2025	MCRB Seres Therapeutics, Inc.	Exercise(M)	133	-	-	Direct
Aug 15, 2025	MCRB Seres Therapeutics, Inc.	Exercise(M)	111	-	-	Direct
May 15, 2025	MCRB Seres Therapeutics, Inc.	Exercise(M)	133	-	-	Direct
May 15, 2025	MCRB Seres Therapeutics, Inc.	Sale(S)	79	$7.28	$575	Direct
May 15, 2025	MCRB Seres Therapeutics, Inc.	Exercise(M)	111	-	-	Direct
Feb 18, 2025	MCRB Seres Therapeutics, Inc.	Sale(S)	4,300	$0.81	$3,485	Direct
Feb 15, 2025	MCRB Seres Therapeutics, Inc.	Exercise(M)	2,657	-	-	Direct
Feb 15, 2025	MCRB Seres Therapeutics, Inc.	Exercise(M)	8,907	-	-	Direct
Feb 7, 2025	MCRB Seres Therapeutics, Inc.	Award(A) Stock Option (Right to Buy)	650,000	-	-	Direct
Nov 18, 2024	MCRB Seres Therapeutics, Inc.	Sale(S)	878	$0.54	$475	Direct
Nov 15, 2024	MCRB Seres Therapeutics, Inc.	Exercise(M)	2,656	-	$0	Direct
Oct 28, 2024	MCRB Seres Therapeutics, Inc.	Sale(S)	4,259	$0.69	$2,939	Direct
Oct 27, 2024	MCRB Seres Therapeutics, Inc.	Exercise(M)	13,500	-	$0	Direct

1-25 of 25 transactions

About DesRosier Thomas

DesRosier Thomas (SEC CIK 0001435744) files insider reports with the SEC as Officer of Seres Therapeutics, Inc. (MCRB).

Signal8 holds 12 ownership filings by DesRosier Thomas, all Form 4s, filed between Oct 29, 2024 and Aug 18, 2026. Those filings report 25 transactions, from Oct 27, 2024 to Aug 17, 2026. Signal8's Form 4 history starts in Sep 2024.

The business address on DesRosier Thomas's filings is in CAMBRIDGE, MA.

Recent filings by DesRosier Thomas

Aug 17, 2026: Open-market sale of MCRB shares (Form 4, code S).
Aug 15, 2026: Option exercise of MCRB shares (Form 4, code M).
Jul 8, 2026: Grant or award of MCRB derivative securities (Form 4, code A).
May 18, 2026: Open-market sale of MCRB shares (Form 4, code S).
May 15, 2026: Option exercise of MCRB shares (Form 4, code M).

Other insiders filing for Seres Therapeutics, Inc. (MCRB)

How to read Form 4 transaction codes