Terrestrial Energy
IMSR
66 hedge funds and large institutions have $163M invested in Terrestrial Energy in 2025 Q3 according to their latest regulatory filings, with 33 funds opening new positions, 14 increasing their positions, 18 reducing their positions, and 32 closing their positions.
54% more call options, than puts
Call options by funds: $16.9M | Put options by funds: $10.9M
2% more funds holding
Funds holding: 65 → 66 (+1)
3% more first-time investments, than exits
New positions opened: 33 | Existing positions closed: 32
22% less repeat investments, than reductions
Existing positions increased: 14 | Existing positions reduced: 18
22% less capital invested
Capital invested by funds: $210M → $163M (-$47.1M)
38.67% less ownership
Funds ownership: 81.72% → 43.06% (-39%)
50% less funds holding in top 10
Funds holding in top 10: 2 → 1 (-1)
Top Buyers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
Citadel Advisors
Miami,
Florida
|
+$11.4M |
| 2 |
Susquehanna International Group
Bala Cynwyd,
Pennsylvania
|
+$6.98M |
| 3 |
Millennium Management
New York
|
+$5.11M |
| 4 |
Balyasny Asset Management
Chicago,
Illinois
|
+$3.8M |
| 5 |
DKCM
Davidson Kempner Capital Management
New York
|
+$3.22M |
Top Sellers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
LA
Linden Advisors
New York
|
-$20.7M |
| 2 |
MF
Magnetar Financial
Evanston,
Illinois
|
-$14.9M |
| 3 |
FTCM
First Trust Capital Management
Chicago,
Illinois
|
-$11.7M |
| 4 |
PMAM
Picton Mahoney Asset Management
Toronto,
Ontario, Canada
|
-$10.7M |
| 5 |
MI
MMCAP International
Grand Cayman,
Cayman Islands
|
-$10.7M |
IMSR Hedge Fund Activity: Q3 2025 in Review
66 of the 7,642 institutional investors tracked by Wall St. Rank reported a position in Terrestrial Energy (IMSR) for Q3 2025, worth a combined $163M — down 22% from $210M a quarter earlier.
Buyers outnumbered sellers: 33 funds opened new IMSR positions and 32 closed out — a net gain of 1 holder — while 14 added to existing stakes and 18 trimmed.
The largest buyer was Citadel Advisors, adding an estimated $11.4M. The largest seller was Linden Advisors, cutting an estimated $20.7M.
- 66 institutional investors held Terrestrial Energy (IMSR) as of Q3 2025, up from 65 in Q2 2025.
- Funds reported $163M of Terrestrial Energy stock for Q3 2025, down 22% quarter-over-quarter.
- 33 funds opened new Terrestrial Energy positions in Q3 2025 and 32 closed out, a net change of +1 holder.
- The largest Terrestrial Energy buyer in Q3 2025 was Citadel Advisors, an estimated $11.4M added.
- The largest Terrestrial Energy seller in Q3 2025 was Linden Advisors, an estimated $20.7M sold.
Based on aggregated 13F filings for Q3 2025.