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Terrestrial Energy Inc.

IMSR
Exchange
Nasdaq
Industry
Fabricated Plate Work (Boiler Shops)
SEC CIK
0002019804

No open-market purchases or sales by Terrestrial Energy Inc. insiders were filed in the last 90 days; 110 institutions reported holding it in 13F filings for Q2 2026, worth $151.3M in total; no superinvestor holds it.

Other share classesIMSRW

13F holders, Q2 2025

Institutional positions in Terrestrial Energy Inc. as of Jun 30, 2025. Investment managers with $100 million or more in US stocks report their long positions on Form 13F within 45 days after each quarter ends. How 13F works

Institutional holders
65
+21 vs. Q1 2025
Shares held
18.8M
−1.42M (−7.0%) vs. Q1 2025
Total value
$209.6M
−$3.53M (−1.7%) vs. Q1 2025
New holders
29
7 more added
Sold out
8
23 more reduced

1 institution that held it in Q1 2025 haven't filed for Q2 2025 yet. Not filing isn't selling, so they aren't counted as sold out or in the changes above.

Compare with Q1 2025: new holders, sold out and not filed yet

Holders and value by quarter

Institutions reporting IMSR on Form 13F each quarter since Q1 2021, and the total value they reported. Values are as of each quarter end, so they also move with the share price.

Institutional holdersQ2 2025: 65 institutions
Q1 2021: 0 institutionsQ2 2021: 0 institutionsQ3 2021: 0 institutionsQ4 2021: 0 institutionsQ1 2022: 0 institutionsQ2 2022: 0 institutionsQ3 2022: 0 institutionsQ4 2022: 0 institutionsQ1 2023: 0 institutionsQ2 2023: 0 institutionsQ3 2023: 0 institutionsQ4 2023: 0 institutionsQ1 2024: 0 institutionsQ2 2024: 0 institutionsQ3 2024: 0 institutionsQ4 2024: 35 institutionsQ1 2025: 45 institutionsQ2 2025: 65 institutionsQ3 2025: 66 institutionsQ4 2025: 82 institutionsQ1 2026: 88 institutionsQ2 2026: 110 institutions
Value heldQ2 2025: $209.6M
Q1 2021: $0Q2 2021: $0Q3 2021: $0Q4 2021: $0Q1 2022: $0Q2 2022: $0Q3 2022: $0Q4 2022: $0Q1 2023: $0Q2 2023: $0Q3 2023: $0Q4 2023: $0Q1 2024: $0Q2 2024: $0Q3 2024: $0Q4 2024: $162.3MQ1 2025: $213.4MQ2 2025: $209.6MQ3 2025: $162.5MQ4 2025: $130.7MQ1 2026: $111.3MQ2 2026: $151.3M
Institutions holding IMSR and their total value by quarter
QuarterHoldersValue
Q2 2026110$151.3M
Q1 202688$111.3M
Q4 202582$130.7M
Q3 202566$162.5M
Q2 202565$209.6M
Q1 202545$213.4M
Q4 202435$162.3M
Q3 20240$0
Q2 20240$0
Q1 20240$0
Q4 20230$0
Q3 20230$0
Q2 20230$0
Q1 20230$0
Q4 20220$0
Q3 20220$0
Q2 20220$0
Q1 20220$0
Q4 20210$0
Q3 20210$0
Q2 20210$0
Q1 20210$0

Institutions, Q2 2025

Shares, value and share of portfolio for each institution holding Terrestrial Energy Inc.; share changes are against Q1 2025.

Institutions holding IMSR in Q2 2025
InstitutionSharesValue% of portfolioChange in sharesAction
Linden Advisors LP1,950,000$21.6M0.13%−50,000−2.5%Reduced
Magnetar Financial LLC1,397,166$16.5M0.08%−562,032−28.7%Reduced
Vivaldi Asset Management, LLC1,051,124$11.7M0.79%−677,828−39.2%Reduced
Vennlight Capital Management, LP1,027,934$11.4M12.52%+1,027,934New
D. E. Shaw & Co., Inc.970,000$10.8M0.01%00.0%Unchanged
MMCAP International Inc. SPC962,068$10.7M1.28%−17,932−1.8%Reduced
Picton Mahoney Asset Management942,081$10.5M0.15%−837,919−47.1%Reduced
LMR Partners LLP941,287$10.4M0.16%−470,402−33.3%Reduced
Arosa Capital Management LP560,000$6.22M4.54%+560,000New
Shay Capital LLC548,258$6.09M1.39%+548,258New
Balyasny Asset Management LLC544,894$6.05M0.01%+479,894+738.3%Added
Calamos Advisors LLC500,000$5.55M0.02%00.0%Unchanged
DLD Asset Management, LP468,825$5.20M0.62%+239,189+104.2%Added
Cantor Fitzgerald, L. P.466,287$5.18M0.13%+466,287New
Goldman Sachs Group Inc435,071$4.83M0.00%−183,701−29.7%Reduced
Commonwealth of Pennsylvania Public School Empls Retrmt Sys405,962$4.51M0.02%00.0%Unchanged
Rivernorth Capital Management, LLC400,000$4.44M0.25%00.0%Unchanged
Berkley W R Corp398,021$4.42M0.27%+100,781+33.9%Added
Senator Investment Group LP340,000$3.77M0.15%+340,000New
Whitebox Advisors LLC318,914$3.54M0.10%−81,086−20.3%Reduced
MYDA Advisors LLC300,000$3.33M0.93%+300,000New
Governors Lane LP300,000$3.33M0.46%+300,000New
Polar Asset Management Partners Inc.257,307$2.86M0.07%−98,538−27.7%Reduced
PEAK6 LLC253,361$2.81M0.10%+253,361New
HRT Financial LP230,069$2.55M0.01%+130,749+131.6%Added
Millennium Management LLC200,000$2.22M0.00%00.0%Unchanged
Scoggin Management LP200,000$2.22M1.03%+200,000New
Westchester Capital Management, LLC199,691$2.22M0.13%−470,790−70.2%Reduced
J. Goldman & Co LP176,249$1.96M0.06%+176,249New
Gritstone Asset Management LLC173,847$1.93M1.91%−50,000−22.3%Reduced
Verition Fund Management LLC150,000$1.67M0.01%−32,612−17.9%Reduced
Mint Tower Capital Management B.V.144,903$1.61M0.25%00.0%Unchanged
Tenor Capital Management Co., L.P.142,960$1.59M0.02%−32,040−18.3%Reduced
Geode Capital Management, LLC121,373$1.35M0.00%+121,373New
Bulldog Investors, LLP113,348$1.26M0.32%−162,555−58.9%Reduced
Deltec Asset Management LLC100,000$1.11M0.20%−15,000−13.0%Reduced
Wexford Capital LP100,000$1.11M0.31%+100,000New
Massar Capital Management, LP100,000$1.11M0.83%+100,000New
Hidden Lake Asset Management LP99,370$1.10M0.54%+99,370New
Periscope Capital Inc.85,000$943.5K0.36%−70,000−45.2%Reduced
Wolverine Asset Management LLC83,869$930.9K0.02%−170,160−67.0%Reduced
Bluefin Capital Management, LLC74,665$828.8K0.64%+74,665New
Morgan Stanley70,969$787.8K0.00%+50,969+254.8%Added
Citadel Advisors LLC69,721$773.9K0.00%+69,721New
Context Capital Management, LLC54,800$608.3K0.02%−245,200−81.7%Reduced
Shaolin Capital Management LLC50,000$555.0K0.02%+50,000New
JPMorgan Chase & Co49,740$552.1K0.00%+49,740New
Fifth Lane Capital, LP45,000$499.5K0.60%+45,000New
FNY Investment Advisers, LLC41,500$460.0K0.20%+41,400+41,400.0%Added
Yaupon Capital Management LP35,139$390.0K0.03%+35,139New
Toronto Dominion Bank34,485$382.8K0.00%−40,960−54.3%Reduced
Virtu Financial LLC21,838$242.0K0.01%+8,298+61.3%Added
Patriot Financial Group Insurance Agency, LLC18,850$209.2K0.02%+18,850New
Susquehanna International Group, LLP15,146$168.1K0.00%−25,145−62.4%Reduced
Tuttle Tactical Management15,000$166.5K0.69%−20,000−57.1%Reduced
National Bank of Canada12,568$139.5K0.00%+12,568New
Schonfeld Strategic Advisors LLC11,394$126.5K0.00%−33,615−74.7%Reduced
North Capital, Inc.6,000$66.6K0.06%+6,000New
UBS Group AG3,648$40.5K0.00%−27,402−88.3%Reduced
Gordian Capital Singapore Pte Ltd3,000$33.3K0.05%+3,000New
Anchor Investment Management, LLC2,100$23.3K0.00%+2,100New
Federation des caisses Desjardins du Quebec1,200$13.3K0.00%+1,200New
Advisor Group Holdings, Inc.200$2.22K0.00%+200New
Tower Research Capital LLC (TRC)105$1.17K0.00%+105New
Citigroup Inc50$5550.00%+50New
CNH Partners LLC0$00.00%−1,288,674−100.0%Sold out
Encompass Capital Advisors LLC0$00.00%−946,165−100.0%Sold out
Two Sigma Investments, LP0$00.00%−500,000−100.0%Sold out
Athos Capital Ltd0$00.00%−200,000−100.0%Sold out
Decagon Asset Management LLP0$00.00%−56,178−100.0%Sold out
Glazer Capital, LLC0$00.00%−36,831−100.0%Sold out
PenderFund Capital Management Ltd.0$00.00%−30,000−100.0%Sold out
Clear Street LLC0$00.00%−165−100.0%Sold out
Mizuho Securities USA LLC––––Not filed