0002019804 2026-10-30 2026-10-30 0002019804 1 2026-10-30 2026-10-30 iso4217:USD pure shares S-3 S-3 EX-FILING FEES 0002019804 Terrestrial Energy Inc. /DE/ N/A N/A S-3 Terrestrial Energy Inc. /DE/ false Equity Common Stock, par value $0.0001 per share true 2263805 3.29 7447918.45 0.000087 647.97 7447918.45 647.97 0.00 0.00 647.97 (1) Any additional shares of common stock of Terrestrial Energy Inc. (the "Registrant") to be issued as a result of stock dividends, stock splits or similar transactions shall be covered by this Registration Statement as provided in Rule 416(a) under the Securities Act of 1933, as amended. (2) Calculated in accordance with Rule 457(c) under the Securities Act of 1933 solely for the purpose of calculating the registration fee, which is based on the average of the high and low market prices of the shares of common stock of the Registrant as reported on the Nasdaq Stock Market LLC on October 27, 2026, which date was within five business days prior to the filing of this Registration Statement. (3) Represents an aggregate of 2,263,805 shares of the Registrant's common stock, par value $0.0001 per share ("Common Stock") registered for resale by the selling stockholder identified in the prospectus and issuable upon exercise of stock options awarded to him during his employment with Terrestrial Energy Development, Inc., before its business combination with the Registrant.