Terrestrial Energy
IMSR
82 hedge funds and large institutions have $131M invested in Terrestrial Energy in 2025 Q4 according to their latest regulatory filings, with 50 funds opening new positions, 19 increasing their positions, 9 reducing their positions, and 34 closing their positions.
250% more call options, than puts
Call options by funds: $22.1M | Put options by funds: $6.33M
111% more repeat investments, than reductions
Existing positions increased: 19 | Existing positions reduced: 9
47% more first-time investments, than exits
New positions opened: 50 | Existing positions closed: 34
24% more funds holding
Funds holding: 66 → 82 (+16)
16.87% less ownership
Funds ownership: 43.06% → 26.19% (-17%)
20% less capital invested
Capital invested by funds: $163M → $131M (-$31.8M)
100% less funds holding in top 10
Funds holding in top 10: 1 → 0 (-1)
Top Buyers
| 1 |
Vanguard Group
Malvern,
Pennsylvania
|
+$24.7M |
| 2 |
JP Morgan Chase
New York
|
+$14.9M |
| 3 |
BlackRock
New York
|
+$14.6M |
| 4 |
Citadel Advisors
Miami,
Florida
|
+$13.4M |
| 5 |
SIG
Senator Investment Group
New York
|
+$12M |
Top Sellers
| 1 |
Millennium Management
New York
|
-$7.99M |
| 2 |
VCM
Vennlight Capital Management
Weston,
Connecticut
|
-$6.68M |
| 3 |
DKCM
Davidson Kempner Capital Management
New York
|
-$4.44M |
| 4 |
SG
Sourcerock Group
Denver,
Colorado
|
-$4.23M |
| 5 |
SCM
SIR Capital Management
New York
|
-$3.57M |
IMSR Hedge Fund Activity: Q4 2025 in Review
82 of the 8,223 institutional investors tracked by Wall St. Rank reported a position in Terrestrial Energy (IMSR) for Q4 2025, worth a combined $131M — down 20% from $163M a quarter earlier.
Buyers outnumbered sellers: 50 funds opened new IMSR positions and 34 closed out — a net gain of 16 holders — while 19 added to existing stakes and 9 trimmed.
The largest buyer was Vanguard Group, opening a new position worth an estimated $24.7M. The largest seller was Millennium Management, cutting an estimated $7.99M.
- 82 institutional investors held Terrestrial Energy (IMSR) as of Q4 2025, up from 66 in Q3 2025.
- Funds reported $131M of Terrestrial Energy stock for Q4 2025, down 20% quarter-over-quarter.
- 50 funds opened new Terrestrial Energy positions in Q4 2025 and 34 closed out, a net change of +16 holders.
- The largest Terrestrial Energy buyer in Q4 2025 was Vanguard Group, an estimated $24.7M added.
- The largest Terrestrial Energy seller in Q4 2025 was Millennium Management, an estimated $7.99M sold.
Based on aggregated 13F filings for Q4 2025.