Ranked by reported Q1 2026 13F market value
Share of total reported institutional value in HDSN held by the largest 10 / 25 filers.
| # | Institution | Shares Held | Market Value | QoQ Change | Ownership % | % of Fund |
|---|---|---|---|---|---|---|
| 1 | Hartree Partners, LP | 3.8M | $22.3M | 0.0% | 8.948% | 4.83% |
| 2 | WESTERLY CAPITAL MANAGEMENT, LLC | 3.2M | $18.7M | +24.5% | 7.476% | 5.75% |
| 3 | BlackRock, Inc. | 2.9M | $16.8M | -1.8% | 6.740% | 0.00% |
| 4 | DIMENSIONAL FUND ADVISORS LP | 2.1M | $12.6M | +5.1% | 5.059% | 0.00% |
| 5 | VANGUARD CAPITAL MANAGEMENT LLC | 1.7M | $9.8M | — | 3.909% | 0.00% |
| 6 | RENAISSANCE TECHNOLOGIES LLC | 1.5M | $8.8M | -11.4% | 3.542% | 0.01% |
| 7 | AMERICAN CENTURY COMPANIES INC | 1.5M | $8.7M | +7.3% | 3.503% | 0.00% |
| 8 | NEW SOUTH CAPITAL MANAGEMENT INC | 1.2M | $7.3M | -3.3% | 2.923% | 0.35% |
| 9 | GEODE CAPITAL MANAGEMENT, LLC | 949K | $5.6M | +0.6% | 2.234% | 0.00% |
| 10 | STATE STREET CORP | 898K | $5.3M | +0.4% | 2.114% | 0.00% |
| 11 | ARROWSTREET CAPITAL, LIMITED PARTNERSHIP | 881K | $5.2M | -10.3% | 2.075% | 0.00% |
| 12 | CASPIAN CAPITAL LP | 728K | $4.3M | 0.0% | 1.715% | 4.17% |
| 13 | BRIDGEWAY CAPITAL MANAGEMENT, LLC | 498K | $2.9M | +31.7% | 1.173% | 0.06% |
| 14 | MORGAN STANLEY | 472K | $2.8M | -33.1% | 1.111% | 0.00% |
| 15 | CITADEL ADVISORS LLC | 424K | $2.5M | +430.0% | 0.999% | 0.00% |
| 16 | PUBLIC EMPLOYEES RETIREMENT SYSTEM OF OHIO | 410K | $2.4M | 0.0% | 0.966% | 0.01% |
| 17 | NORTHERN TRUST CORP | 399K | $2.3M | +1.9% | 0.940% | 0.00% |
| 18 | Qube Research & Technologies Ltd | 371K | $2.2M | +126.6% | 0.873% | 0.00% |
| 19 | D. E. Shaw & Co., Inc. | 359K | $2.1M | -38.5% | 0.845% | 0.00% |
| 20 | AQR CAPITAL MANAGEMENT LLC | 344K | $2.0M | +1.5% | 0.811% | 0.00% |
| 21 | LAZARD ASSET MANAGEMENT LLC | 326K | $1.9M | -24.5% | 0.767% | 0.00% |
| 22 | 683 Capital Management, LLC | 325K | $1.9M | -3.0% | 0.765% | 0.15% |
| 23 | JB CAPITAL PARTNERS LP | 306K | $1.8M | 0.0% | 0.721% | 0.31% |
| 24 | Bank of New York Mellon Corp | 282K | $1.7M | -13.3% | 0.665% | 0.00% |
| 25 | TWO SIGMA INVESTMENTS, LP | 273K | $1.6M | +101.6% | 0.643% | 0.00% |
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 HDSN — a direct measure of their conviction.
Filings activity in HDSN during Q1 2026, grouped by how each filer changed its position.
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 |
|---|---|---|---|---|---|---|
| Q1 2026 | 156 | 7.7% | 76.47% | 37.46 pp | $188M | 33% |
| Q4 2025 | 169 | +1.8% | 113.93% | 17.62 pp | $280M | 13% |
| Q3 2025 | 166 | +13% | 131.55% | +24.04 pp | $323M | +22% |
| Q2 2025 | 147 | 8.1% | 107.51% | +30.03 pp | $264M | +39% |
| Q1 2025 | 160 | 3.0% | 77.48% | +12.09 pp | $190M | +18% |
| Q4 2024 | 165 | 3.5% | 65.39% | 31.97 pp | $161M | 33% |
| Q3 2024 | 171 | +8.2% | 97.36% | 8.26 pp | $239M | 7.8% |
| Q2 2024 | 158 | — | 105.62% | — | $259M | — |
Source: SEC 13F institutional filings. Ownership % requires market cap data and will show once linked. Δ columns compare to the immediately prior filed quarter.
Latest Form 4 transactions by company officers and directors. Insider buys are widely viewed as the highest-conviction signal because executives are risking personal capital.
| Date | Insider | Action | Shares | Price | Value |
|---|---|---|---|---|---|
| May 19, 2026 | Bertaux Brian J. | Buy | 2K | $4.87 | $10K |
| May 14, 2026 | Mansy Loan Nguyen | Buy | 4K | $4.96 | $18K |
| May 14, 2026 | Parrillo Richard | Buy | 4K | $4.96 | $18K |
| May 14, 2026 | Bulgarino Nicole E | Buy | 550 | $4.84 | $3K |
| May 14, 2026 | Feeler Jeffrey R | Buy | 5K | $4.92 | $25K |
| May 13, 2026 | Sheriff Alan | Buy | 5K | $4.88 | $25K |
Quick answers to the most common questions about buying HDSN stock.
Based on Q1 2026 13F filings, institutional ownership of Hudson Technologies, Inc. stands at 76.5%, held across 156 reporting institutions.
Hartree Partners, LP is the largest reported institutional holder of HDSN, with approximately 3,800,000 shares worth $0.02B as of Q1 2026.
Yes — 3 widely-followed marquee investors appear among the top 25 institutional holders of HDSN, including RENAISSANCE TECHNOLOGIES LLC, CITADEL ADVISORS LLC, TWO SIGMA INVESTMENTS, LP.
Our composite Smart Money Score for HDSN is 44 out of 100 (Neutral). It combines net institutional buying activity, ownership shift, marquee investor presence, and holder-count growth.
25 institutions opened new positions in HDSN during Q1 2026, while 38 fully exited. 26 added to existing positions and 103 trimmed.
HDSN institutional ownership fell by 37.46 percentage points quarter-over-quarter, with a net change of -13 holders.
The top 10 institutions account for 61.8% of all reported 13F value in HDSN, and the top 25 account for 81.8%.
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.
Hudson Technologies, Inc. (HDSN) Institutional Ownership