Ranked by reported Q2 2026 13F market value
Share of total reported institutional value in PESI held by the largest 10 / 25 filers.
| # | Institution | Shares Held | Market Value | QoQ Change | Ownership % | % of Fund |
|---|---|---|---|---|---|---|
| 1 | BlackRock, Inc. | 1.3M | $17.9M | +7.0% | 5.908% | 0.00% |
| 2 | MAK CAPITAL ONE LLC | 1.0M | $14.8M | +12.4% | 4.872% | 2.07% |
| 3 | VANGUARD CAPITAL MANAGEMENT LLC | 812K | $11.6M | +6.9% | 3.828% | 0.00% |
| 4 | PRESCOTT GROUP CAPITAL MANAGEMENT, L.L.C. | 777K | $11.1M | 0.0% | 3.665% | 0.96% |
| 5 | Diamond Hill Capital Management, LLC (Investment Advisor) | 643K | $9.2M | +80.5% | 3.030% | 0.07% |
| 6 | KENNEDY CAPITAL MANAGEMENT LLC | 611K | $8.7M | — | 2.881% | 0.15% |
| 7 | Potomac Capital Management, Inc. | 477K | $6.8M | +60.8% | 2.250% | 4.65% |
| 8 | GEODE CAPITAL MANAGEMENT, LLC | 455K | $6.5M | +5.2% | 2.147% | 0.00% |
| 9 | HEARTLAND ADVISORS INC | 400K | $5.7M | 0.0% | 1.887% | 0.25% |
| 10 | STATE STREET CORP | 350K | $5.0M | +4.2% | 1.649% | 0.00% |
| 11 | SUSQUEHANNA INTERNATIONAL GROUP, LLP | 250K | $3.6M | +54.5% | 1.178% | 0.00% |
| 12 | DIMENSIONAL FUND ADVISORS LP | 191K | $2.7M | +16.7% | 0.901% | 0.00% |
| 13 | CITADEL ADVISORS LLC | 166K | $2.4M | +96.2% | 0.785% | 0.00% |
| 14 | GOLDMAN SACHS GROUP INC | 163K | $2.3M | +14.1% | 0.768% | 0.00% |
| 15 | NORTHERN TRUST CORP | 142K | $2.0M | +9.3% | 0.668% | 0.00% |
| 16 | VANGUARD FIDUCIARY TRUST CO | 123K | $1.8M | +3.2% | 0.580% | 0.00% |
| 17 | GROUP ONE TRADING LLC | 123K | $1.8M | -50.5% | 0.578% | 0.00% |
| 18 | VANGUARD PORTFOLIO MANAGEMENT LLC | 121K | $1.7M | +20.9% | 0.572% | 0.00% |
| 19 | North Star Investment Management Corp. | 121K | $1.7M | 0.0% | 0.569% | 0.09% |
| 20 | Diametric Capital, LP | 115K | $1.6M | — | 0.541% | 0.17% |
| 21 | MYDA Advisors LLC | 90K | $1.3M | -25.0% | 0.424% | 0.19% |
| 22 | CM WEALTH ADVISORS LLC | 88K | $1.3M | — | 0.414% | 0.23% |
| 23 | XTX Topco Ltd | 63K | $899K | +170.8% | 0.297% | 0.01% |
| 24 | Owls Nest Partners IA, LLC | 57K | $808K | — | 0.267% | 0.26% |
| 25 | Pale Fire Capital SE | 56K | $795K | +14.4% | 0.262% | 0.06% |
denotes a marquee investor (Buffett, Burry, ARK, Tiger Global, Pershing Square, Baupost and other widely-followed managers). “% of Fund” shows how much of that investor’s total 13F portfolio is invested in PESI — a direct measure of their conviction.
Filings activity in PESI during Q2 2026, grouped by how each filer changed its position.
Institutions that opened a new PESI position in Q2 2026
Institutions that fully closed their PESI position in Q2 2026
8 quarters of 13F filings · Δ columns show change vs prior quarter
| Quarter | Inst. Holders | Δ Holders | Ownership % | Δ Ownership | Total 13F Value | Δ Value |
|---|---|---|---|---|---|---|
| Q2 2026 | 89 | +3.5% | 45.28% | +8.49 pp | $137M | +65% |
| Q1 2026 | 86 | +4.9% | 36.79% | 0.09 pp | $83M | 15% |
| Q4 2025 | 82 | +6.5% | 36.88% | +1.11 pp | $98M | +32% |
| Q3 2025 | 77 | +12% | 35.77% | 3.52 pp | $74M | +10% |
| Q2 2025 | 69 | 8.0% | 39.29% | +8.04 pp | $67M | +48% |
| Q1 2025 | 75 | +2.7% | 31.25% | 3.63 pp | $46M | 41% |
| Q4 2024 | 73 | +7.4% | 34.88% | +2.86 pp | $77M | +16% |
| Q3 2024 | 68 | — | 32.02% | — | $66M | — |
Source: SEC 13F institutional filings. Ownership % requires market cap data and will show once linked. Δ columns compare to the immediately prior filed quarter.
Quick answers to the most common questions about buying PESI stock.
Based on Q2 2026 13F filings, institutional ownership of Perma-Fix Environmental Services, Inc. stands at 45.3%, held across 89 reporting institutions.
BlackRock, Inc. is the largest reported institutional holder of PESI, with approximately 1,252,756 shares worth $0.02B as of Q2 2026.
Yes — 2 widely-followed marquee investors appear among the top 25 institutional holders of PESI, including SUSQUEHANNA INTERNATIONAL GROUP, LLP, CITADEL ADVISORS LLC.
Our composite Smart Money Score for PESI is 68 out of 100 (Bullish). It combines net institutional buying activity, ownership shift, marquee investor presence, and holder-count growth.
13 institutions opened new positions in PESI during Q2 2026, while 9 fully exited. 66 added to existing positions and 9 trimmed.
PESI institutional ownership rose by 8.49 percentage points quarter-over-quarter, with a net change of +3 holders.
The top 10 institutions account for 71.1% of all reported 13F value in PESI, and the top 25 account for 90.6%.
All data is sourced from SEC Form 13F filings, which institutional investment managers with at least $100M in assets are required to file each quarter. We process every 13F filing from EDGAR and recompute the aggregates after each cycle. Insider transactions are sourced from Form 4 filings.
Perma-Fix Environmental Services, Inc. (PESI) Institutional Ownership