Perma-Fix Environmental Services
PESI
84 hedge funds and large institutions have $99.2M invested in Perma-Fix Environmental Services in 2025 Q4 according to their latest regulatory filings, with 14 funds opening new positions, 23 increasing their positions, 27 reducing their positions, and 7 closing their positions.
100% more funds holding in top 10
Funds holding in top 10: 1 → 2 (+1)
100% more first-time investments, than exits
New positions opened: 14 | Existing positions closed: 7
49% more call options, than puts
Call options by funds: $791K | Put options by funds: $530K
32% more capital invested
Capital invested by funds: $75M → $99.2M (+$24.2M)
9% more funds holding
Funds holding: 77 → 84 (+7)
2.36% more ownership
Funds ownership: 40.18% → 42.53% (+2.4%)
15% less repeat investments, than reductions
Existing positions increased: 23 | Existing positions reduced: 27
Top Buyers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
SL
Sentinus LLC
Oak Brook,
Illinois
|
+$2.12M |
| 2 |
MCO
MAK Capital One
New York
|
+$1.31M |
| 3 |
MA
MYDA Advisors
Woodmere,
New York
|
+$1.27M |
| 4 |
Jane Street
New York
|
+$1.1M |
| 5 |
Susquehanna International Group
Bala Cynwyd,
Pennsylvania
|
+$1.03M |
Top Sellers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
VanEck Associates
New York
|
-$2.23M |
| 2 |
EIM
Essex Investment Management
Boston,
Massachusetts
|
-$1.98M |
| 3 |
AA
Ancora Advisors
Cleveland,
Ohio
|
-$1.18M |
| 4 |
HA
Heartland Advisors
Milwaukee,
Wisconsin
|
-$742K |
| 5 |
LCM
Legato Capital Management
San Francisco,
California
|
-$570K |
PESI Hedge Fund Activity: Q4 2025 in Review
84 of the 8,223 institutional investors tracked by Wall St. Rank reported a position in Perma-Fix Environmental Services (PESI) for Q4 2025, worth a combined $99.2M — up 32% from $75M a quarter earlier.
Buyers outnumbered sellers: 14 funds opened new PESI positions and 7 closed out — a net gain of 7 holders — while 23 added to existing stakes and 27 trimmed.
The largest buyer was Sentinus LLC, opening a new position worth an estimated $2.12M. The largest seller was VanEck Associates, exiting entirely with an estimated $2.23M sold.
- 84 institutional investors held Perma-Fix Environmental Services (PESI) as of Q4 2025, up from 77 in Q3 2025.
- Funds reported $99.2M of Perma-Fix Environmental Services stock for Q4 2025, up 32% quarter-over-quarter.
- 14 funds opened new Perma-Fix Environmental Services positions in Q4 2025 and 7 closed out, a net change of +7 holders.
- The largest Perma-Fix Environmental Services buyer in Q4 2025 was Sentinus LLC, an estimated $2.12M added.
- The largest Perma-Fix Environmental Services seller in Q4 2025 was VanEck Associates, an estimated $2.23M sold.
Based on aggregated 13F filings for Q4 2025.