Terrestrial Energy Inc. has 13 Schedule 13D or 13G filings on record since 2025-08-06. 3 holders' latest filing reports 5% or more of common stock, par value $0.0001 per share (the "shares"). Each figure below is the holder's own, as filed, with the filing linked.
Holders
| Holder | Percent | Shares | Latest | Event date |
|---|---|---|---|---|
| Roberto Marco Sella | 14.34% | 15,378,689 | SCHEDULE 13G, 2026-01-22 | 2025-10-29 |
| Simon Irish | 12.8% | 13,586,445 | SCHEDULE 13D, 2025-11-04 | 2025-10-28 |
| David LeBlanc | 9.7% | 11,400,410 | SCHEDULE 13D, 2025-11-04 | 2025-10-28 |
| First Trust Capital Management L.P. | 4.66% | 1,071,124 | SCHEDULE 13G/A, 2025-08-14 | 2025-06-30 |
| Picton Mahoney Asset Management | 4.1% | 942,081 | SCHEDULE 13G/A, 2025-08-06 | 2025-06-30 |
| LMR Partners LLP | 4.1% | 941,287 | SCHEDULE 13G/A, 2025-08-14 | 2025-06-30 |
| Merus Global Investments, LLC | 3.8% | 866,058 | SCHEDULE 13G/A, 2025-08-14 | 2025-06-30 |
| Kenneth Griffin | 2.2% | 2,303,796 | SCHEDULE 13G/A, 2026-02-17 | 2025-12-31 |
| Linden Capital L.P. | 0.9% | 209,426 | SCHEDULE 13G/A, 2025-11-12 | 2025-09-30 |
| Magnetar Financial LLC | 0.62% | 142,304 | SCHEDULE 13G/A, 2025-11-12 | 2025-09-30 |
| AQR Capital Management, LLC | 0.01% | 1,449 | SCHEDULE 13G/A, 2025-08-13 | 2025-06-30 |
Purpose of Transaction (Item 4)
Simon Irish
The Reporting Person acquired the shares reported herein for investment purposes and to incentivize him in connection with his employment with the Issuer. To the extent required by Item 4, the information contained in Item 3 and Item 6 is incorporated herein by reference. The Reporting Person serves as Chief Executive Officer of the Issuer and as a member of the Issuer's Board of Directors and, in such capacities, may have influence over the corporate activities of the Issuer, including activities that may relate to items described in subparagraphs (a) through (j) of Item 4 of Schedule 13D. Subject to the that certain Lock-Up Agreement, as described in Item 6 of this Schedule 13D, and the Issuer's Insider Trading Policy (the "Insider Trading Policy"), the Reporting Person may from time to time buy or sell securities of the Issuer as appropriate for his personal circumstances. Except as described herein, the Reporting Person does not have any present plans or proposals that relate to or would result in any of the transactions described in subparagraphs (a) through (j) of Item 4 of Schedule 13D. However, the Reporting Person reserves the right to formulate in the future plans or proposals that may relate to or result in the transactions described in subparagraphs (a) through (j) of Item 4 of Schedule 13D. The Reporting Person may, from time to time, purchase additional securities of the Issuer either in the open market or in privately negotiated transactions, depending …The first part of Item 4 of the SCHEDULE 13D filed 2025-11-04; the filing has the rest
David LeBlanc
The Reporting Person acquired the shares reported herein for investment purposes and to incentivize him in connection with his employment with the Issuer. To the extent required by Item 4, the information contained in Item 3 and Item 6 is incorporated herein by reference. The Reporting Person serves as Chief Technology Officer of the Issuer and as a member of the Issuer's Board of Directors and, in such capacities, may have influence over the corporate activities of the Issuer, including activities that may relate to items described in subparagraphs (a) through (j) of Item 4 of Schedule 13D. Subject to the that certain Lock-Up Agreement, as described in Item 6 of this Schedule 13D, and the Issuer's Insider Trading Policy (the "Insider Trading Policy"), the Reporting Person may from time to time buy or sell securities of the Issuer as appropriate for his personal circumstances. Except as described herein, the Reporting Person does not have any present plans or proposals that relate to or would result in any of the transactions described in subparagraphs (a) through (j) of Item 4 of Schedule 13D. However, the Reporting Person reserves the right to formulate in the future plans or proposals that may relate to or result in the transactions described in subparagraphs (a) through (j) of Item 4 of Schedule 13D. The Reporting Person may, from time to time, purchase additional securities of the Issuer either in the open market or in privately negotiated transactions, depending …The first part of Item 4 of the SCHEDULE 13D filed 2025-11-04; the filing has the rest
Timeline
| Filed | Holder | Percent | Filing |
|---|---|---|---|
| 2025-08-06 | Picton Mahoney Asset Management | 4.1% | SCHEDULE 13G/A |
| 2025-08-08 | Magnetar Financial LLC | 6.07% | SCHEDULE 13G/A |
| 2025-08-13 | AQR Capital Management, LLC | 0.01% | SCHEDULE 13G/A |
| 2025-08-14 | LMR Partners LLP | 4.1% | SCHEDULE 13G/A |
| 2025-08-14 | Merus Global Investments, LLC | 3.8% | SCHEDULE 13G/A |
| 2025-08-14 | First Trust Capital Management L.P. | 4.66% | SCHEDULE 13G/A |
| 2025-09-30 | Kenneth Griffin | 5.4% | SCHEDULE 13G |
| 2025-11-04 | Simon Irish | 12.8% | SCHEDULE 13D |
| 2025-11-04 | David LeBlanc | 9.7% | SCHEDULE 13D |
| 2025-11-12 | Magnetar Financial LLC | 0.62% | SCHEDULE 13G/A |
| 2025-11-12 | Linden Capital L.P. | 0.9% | SCHEDULE 13G/A |
| 2026-01-22 | Roberto Marco Sella | 14.34% | SCHEDULE 13G |
| 2026-02-17 | Kenneth Griffin | 2.2% | SCHEDULE 13G/A |
Tools for this story
Each opens in a new tab, filled in for Terrestrial Energy Inc.. With no account yet, you sign up free and land on the result.
Where this comes from
Anyone who comes to own more than 5% of a class of a listed company's voting shares has to tell the SEC. A holder who may seek to change or influence the company files Schedule 13D, and has to say in Item 4, "Purpose of Transaction", what it intends to do. A holder with no such intent, such as many index and passive funds, may file the shorter Schedule 13G. Both are amended when the stake changes, including when it falls below 5%.
Every row here is one of those filings, linked to the filing itself. Percentages and share counts are exactly as the holder filed them, for the holder the filing names; an amendment showing a lower figure is shown as filed. Item 4 text is quoted word for word. Where a 13D's Item 4 contains a sentence stating a definite intent to influence the company, that sentence is marked and quoted; the page does not describe the holder or its motives beyond the words it filed. Nothing here is investment advice.