IMSR

Terrestrial Energy Inc. /DE/

Insider trading activity for Terrestrial Energy Inc. /DE/, straight from SEC Form 4 filings. Net figures below count open-market buys and sales only — grants, option exercises and tax withholding are excluded because they are compensation, not decisions to trade.

Past 3 months

net buying

Bought(0 · 0 insiders): $0
Sold(0 · 0 insiders): $0

Past 6 months

net buying

Bought(0 · 0 insiders): $0
Sold(0 · 0 insiders): $0

Past 12 months

net buying

Bought(0 · 0 insiders): $0
Sold(0 · 0 insiders): $0

Transaction history

The 30 most recent Form 4 transactions.

Open in screener →

Insider transactions, newest first: date, security, transaction type, size and a link to the filing each row came from.
Date	Insider	Role	Type	Shares	Price	Value	Δ Own	Filing
Jul 29	Cowan Pamela Beth	EVP, Engineering	AGRANT◆	299,401	—	—	—	Open the original filing on SEC.gov
Jul 23	McCarthy Kathryn Ann	Director	AGRANT◆	2,049	—	—	—	Open the original filing on SEC.gov
Apr 12	Thrasher Brian Patrick	Chief Financial Officer	AGRANT◆	58,236	—	—	—	Open the original filing on SEC.gov
Apr 12	Thrasher Brian Patrick	Chief Financial Officer	AGRANT◆	49,917	—	—	—	Open the original filing on SEC.gov
Apr 12	Smith William F.	Chief Operating Officer	AGRANT◆	32,787	—	—	—	Open the original filing on SEC.gov
Apr 12	Millsap Steven M.	General Counsel	AGRANT◆	49,917	—	—	—	Open the original filing on SEC.gov
Apr 12	LeBlanc David Michael	Chief Technology Officer	AGRANT◆	32,787	—	—	—	Open the original filing on SEC.gov
Dec 18, 2025	Pardee Charles G	Director	AGRANT◆	882	—	—	—	Open the original filing on SEC.gov
Dec 18, 2025	Pardee Charles G	Director	AGRANT◆	5,027	—	—	—	Open the original filing on SEC.gov
Dec 18, 2025	Matthews Shawn	Director	AGRANT◆	735	—	—	—	Open the original filing on SEC.gov
Dec 18, 2025	Matthews Shawn	Director	AGRANT◆	4,190	—	—	—	Open the original filing on SEC.gov
Dec 18, 2025	MacDiarmid John Hugh	Director	AGRANT◆	1,029	—	—	—	Open the original filing on SEC.gov
Dec 18, 2025	MacDiarmid John Hugh	Director	AGRANT◆	5,865	—	—	—	Open the original filing on SEC.gov
Dec 18, 2025	Jones Robert Wood	Director	AGRANT◆	1,029	—	—	—	Open the original filing on SEC.gov
Dec 18, 2025	Jones Robert Wood	Director	AGRANT◆	5,865	—	—	—	Open the original filing on SEC.gov
Dec 18, 2025	Hill David John	Director	AGRANT◆	588	—	—	—	Open the original filing on SEC.gov
Dec 18, 2025	Hill David John	Director	AGRANT◆	3,352	—	—	—	Open the original filing on SEC.gov
Dec 18, 2025	Buckman Frederick W	Director	AGRANT◆	1,176	—	—	—	Open the original filing on SEC.gov
Dec 18, 2025	Buckman Frederick W	Director	AGRANT◆	6,703	—	—	—	Open the original filing on SEC.gov
Dec 18, 2025	Johnson William D	Director	AGRANT◆↺	1,029	—	—	—	Open the original filing on SEC.gov
Nov 6, 2025	Matthews Shawn	Director	JOTHER◆	3.5M	—	—	—	Open the original filing on SEC.gov
Nov 6, 2025	Matthews Shawn	Director	JOTHER	2.9M	—	—	-51.4%	Open the original filing on SEC.gov
Oct 28, 2025	Loveless Jacob	Former Director	JOTHER	25,000	—	—	—	Open the original filing on SEC.gov
Oct 28, 2025	Irish Simon	Chief Executive Officer	AGRANT◆	166,298	—	—	—	Open the original filing on SEC.gov
Oct 28, 2025	Matthews Shawn	Director	JOTHER◆	1.3M	$11.50	$14.6M	—	Open the original filing on SEC.gov
Oct 28, 2025	Matthews Shawn	Director	JOTHER◆	4.3M	$11.50	$49.2M	—	Open the original filing on SEC.gov
Oct 28, 2025	Matthews Shawn	Director	JOTHER	533,514	—	—	—	Open the original filing on SEC.gov
Oct 28, 2025	Matthews Shawn	Director	JOTHER	5.7M	—	—	—	Open the original filing on SEC.gov
Oct 28, 2025	Connor Michael J	Former Director	JOTHER	25,000	—	—	—	Open the original filing on SEC.gov
Oct 28, 2025	Brenner Andrew Scott	Former Director	JOTHER	25,000	—	—	—	Open the original filing on SEC.gov

AGRANT◆—

Cowan Pamela Beth · EVP, EngineeringJul 29

299,401 sh

AGRANT◆—

McCarthy Kathryn Ann · DirectorJul 23

2,049 sh

AGRANT◆—

Thrasher Brian Patrick · Chief Financial…Apr 12

58,236 sh

AGRANT◆—

Thrasher Brian Patrick · Chief Financial…Apr 12

49,917 sh

AGRANT◆—

Smith William F. · Chief Operating…Apr 12

32,787 sh

AGRANT◆—

Millsap Steven M. · General CounselApr 12

49,917 sh

AGRANT◆—

LeBlanc David Michael · Chief Technology…Apr 12

32,787 sh

AGRANT◆—

Pardee Charles G · DirectorDec 18, 2025

882 sh

AGRANT◆—

Pardee Charles G · DirectorDec 18, 2025

5,027 sh

AGRANT◆—

Matthews Shawn · DirectorDec 18, 2025

735 sh

AGRANT◆—

Matthews Shawn · DirectorDec 18, 2025

4,190 sh

AGRANT◆—

MacDiarmid John Hugh · DirectorDec 18, 2025

1,029 sh

AGRANT◆—

MacDiarmid John Hugh · DirectorDec 18, 2025

5,865 sh

AGRANT◆—

Jones Robert Wood · DirectorDec 18, 2025

1,029 sh

AGRANT◆—

Jones Robert Wood · DirectorDec 18, 2025

5,865 sh

AGRANT◆—

Hill David John · DirectorDec 18, 2025

588 sh

AGRANT◆—

Hill David John · DirectorDec 18, 2025

3,352 sh

AGRANT◆—

Buckman Frederick W · DirectorDec 18, 2025

1,176 sh

AGRANT◆—

Buckman Frederick W · DirectorDec 18, 2025

6,703 sh

AGRANT◆↺—

Johnson William D · DirectorDec 18, 2025

1,029 sh

JOTHER◆—

Matthews Shawn · DirectorNov 6, 2025

3.5M sh

JOTHER—

Matthews Shawn · DirectorNov 6, 2025

2.9M sh · -51.4% own

JOTHER—

Loveless Jacob · Former DirectorOct 28, 2025

25,000 sh

AGRANT◆—

Irish Simon · Chief Executive…Oct 28, 2025

166,298 sh

JOTHER◆$14.6M

Matthews Shawn · DirectorOct 28, 2025

1.3M sh @ $11.50

JOTHER◆$49.2M

Matthews Shawn · DirectorOct 28, 2025

4.3M sh @ $11.50

JOTHER—

Matthews Shawn · DirectorOct 28, 2025

533,514 sh

JOTHER—

Matthews Shawn · DirectorOct 28, 2025

5.7M sh

JOTHER—

Connor Michael J · Former DirectorOct 28, 2025

25,000 sh

JOTHER—

Brenner Andrew Scott · Former DirectorOct 28, 2025

25,000 sh

Filing record

How quickly insiders here report their trades. Section 16 allows two business days from the transaction.

1 of 18 filings we hold was filed after the two-business-day deadline. The furthest past the deadline was 1 business day late.

Form 4 filings made after the two-business-day deadline, with the transaction date, the filing date and the number of business days between them.
Traded	Filed	Insider	Past deadline	Largest line	Source
Nov 6, 2025	Nov 12, 2025	HCM Investor Holdings II,… +1Director	1day	—	Filing ↗

HCM Investor Holdings II,… +1Director

1day

Traded Nov 6, 2025 · filed Nov 12, 2025Filing ↗

Counted in business days from the transaction date, or the deemed execution date where the filing reports one, excluding weekends and federal holidays. How this is measured · All late filings

Insiders at this company

Everyone who has filed a Form 4 for this issuer.

More industrials companies

Other issuers in the same industry with insider filings on record.

Whole sector →