{"transactions":[{"id":808950,"issuer":{"id":5288,"kind":"organization","name":"Terrestrial Energy Inc. /DE/","symbol":"IMSR"},"owners":[{"id":52580,"kind":"person","name":"Millsap Steven M.","position":1,"cik":"0002091729","reported_name":"Millsap Steven M.","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"General Counsel"}}],"security":"Restricted Stock Units","published_at":"2026-04-14T22:00:06.000Z","date":"2026-04-12","kind":"grant","planned":false,"acquired":true,"shares":49917,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_price","element":"conversionOrExercisePrice","label":"F1","text":"Each restricted stock unit represents a contingent right to acquire one share of Common Stock."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F2","text":"Consists of restricted stock units granted pursuant to the Terrestrial Energy Inc. 2025 Equity Incentive Plan. The restricted stock units vest in one-third increments on each of the first, second and third anniversaries of the grant date, subject to the reporting person's continued service through each applicable vesting date."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F2","text":"Consists of restricted stock units granted pursuant to the Terrestrial Energy Inc. 2025 Equity Incentive Plan. The restricted stock units vest in one-third increments on each of the first, second and third anniversaries of the grant date, subject to the reporting person's continued service through each applicable vesting date."}],"balance_after":49917,"derivative":{"underlying":"Common Stock","underlying_shares":49917},"source":{"system":"sec-edgar","filing":"0001193125-26-155213","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/2019804/000119312526155213/ownership.xml","form_type":"4"}}]}