Hudson Technologies, Inc.
Hudson Technologies, Inc. (HDSN) Stock Ownership
Institutional vs insider vs public ownership from 13F and float data — top holders, activity, and insider trades below.
SEC 13F · FMP · HDSN · as of Sep 30, 2025
Ownership Breakdown
175
Institutional Holders
▲ 24 vs Q2
$330.45M
Total Inst. Value
▲ $59.79M vs Q2
42.07M
Shares Outstanding
freeFloat 78.55%
33.29M
13F Shares Held
▼ 78,513 vs Q2
Institutional ownership = 13F shares ÷ total outstanding. Insider % = 100 − free float. Public % = free float − institution %. Data: FMP /symbol-positions-summary + /shares-float + SEC EDGAR.
Top Institutional Holders
HDSN largest shareholders · institutional ownership
Q3 2025 · SEC 13F
Showing top 10 holders
| Holder | Shares | % Owned | Weight | Value | Reported | Change |
|---|---|---|---|---|---|---|
HARTREE PARTNERS, LP wholesale-machinery, equipment & supplies | 3.80M | 8.71% | 8.71% | $37.73B | Nov 13, 2025 | ▼ 200.0K |
BLACKROCK, INC. wholesale-machinery, equipment & supplies | 2.86M | 6.56% | 6.56% | $28.43B | Nov 12, 2025 | ▼ 42.6K |
VANGUARD GROUP INC wholesale-machinery, equipment & supplies | 2.37M | 5.44% | 5.44% | $23.57B | Nov 7, 2025 | ▼ 107.1K |
DIMENSIONAL FUND ADVISORS LP wholesale-machinery, equipment & supplies | 2.01M | 4.61% | 4.61% | $19.95B | Nov 12, 2025 | ▲ 2.5K |
WESTERLY CAPITAL MANAGEMENT, LLC wholesale-machinery, equipment & supplies | 1.89M | 4.33% | 4.33% | $18.77B | Nov 14, 2025 | ▼ 110.0K |
RENAISSANCE TECHNOLOGIES LLC wholesale-machinery, equipment & supplies | 1.80M | 4.12% | 4.12% | $17.84B | Nov 13, 2025 | ▲ 125.0K |
NEW SOUTH CAPITAL MANAGEMENT INC wholesale-machinery, equipment & supplies | 1.33M | 3.06% | 3.06% | $13.25B | Nov 6, 2025 | ▼ 16.6K |
AMERICAN CENTURY COMPANIES INC wholesale-machinery, equipment & supplies | 1.27M | 2.92% | 2.92% | $12.65B | Nov 12, 2025 | ▲ 201.1K |
ARROWSTREET CAPITAL, LIMITED PARTNERSHIP wholesale-machinery, equipment & supplies | 1.11M | 2.55% | 2.55% | $11.04B | Nov 13, 2025 | — held |
GEODE CAPITAL MANAGEMENT, LLC wholesale-machinery, equipment & supplies | 954.4K | 2.19% | 2.19% | $9.48B | Nov 12, 2025 | ▲ 10.0K |
Data from SEC Form 13F filings. Ownership bar normalised to largest holder. Change flags: isNew / isSoldOut / changeInSharesNumber (FMP extract-analytics/holder).
Institutional Activity
Q3 2025 vs prior quarter
Q3 2025
24
Increased
+1.73M shares4
New Positions
first time holders17
Decreased
−1.16M shares0
Sold Out
fully exitedNet shares change (top 50)
+564.9K
+1.73M / −1.16M
Net new holders
+11
4 new / 0 exited
Based on top 50 institutional holders by position size. Fields: isNew, isSoldOut, changeInSharesNumber (FMP extract-analytics/holder, limit=50).
Insider Buying vs Selling
HDSN insider trading · insider activity
Source: SEC Form 4
Insiders have been net buyers of shares recently. Selling may be driven by pre-scheduled Rule 10b5-1 plans rather than negative sentiment.
13
Buy transactions
0
Sell transactions
0.00
Buy/Sell ratio
$0M
Total disposed
Recent Insider Transactions
Showing 10 most recent · Common Stock only
| Name · Role | Date | Type | Shares | Price | Value | After Trans. | Filing |
|---|---|---|---|---|---|---|---|
Parrillo Richard director | May 13, 2026 | Purchase | 10,000 | $4.83 | $48.3K | 195.7K | Form 4 ↗ |
Bertaux Brian J. Chief Financial Officer | May 19, 2026 | Purchase | 2,000 | $4.87 | $9.7K | 2.0K | Form 4 ↗ |
Mansy Loan Nguyen director | May 14, 2026 | Purchase | 1,400 | $4.97 | $7.0K | 25.6K | Form 4 ↗ |
Mansy Loan Nguyen director | May 14, 2026 | Purchase | 3,600 | $4.96 | $17.9K | 24.2K | Form 4 ↗ |
Parrillo Richard director | May 14, 2026 | Purchase | 1,400 | $4.97 | $7.0K | 25.6K | Form 4 ↗ |
Parrillo Richard director | May 14, 2026 | Purchase | 3,600 | $4.96 | $17.9K | 24.2K | Form 4 ↗ |
Bulgarino Nicole E director | May 14, 2026 | Purchase | 550 | $4.84 | $2.7K | 11.0K | Form 4 ↗ |
Prouty Eric A director | May 13, 2026 | Purchase | 5,000 | $4.84 | $24.2K | 153.9K | Form 4 ↗ |
Sheriff Alan director | May 13, 2026 | Purchase | 5,200 | $4.88 | $25.4K | 9.3K | Form 4 ↗ |
Feeler Jeffrey R director | May 14, 2026 | Purchase | 5,100 | $4.92 | $25.1K | 9.2K | Form 4 ↗ |
Source: /insider-trading/search (FMP stable). Buy/Sell direction: acquisitionOrDisposition A=Buy, D=Sell. RSU vesting (M-Exempt) excluded from sentiment bar. All data from SEC EDGAR public filings.
About institutional & insider ownership
Hudson Technologies, Inc. (HDSN) is primarily owned by institutional investors, who hold approximately 79.1% of total shares outstanding. Company insiders own approximately 21.45%, while retail and public investors account for the remaining 0.00%.
The largest institutional shareholder of Hudson Technologies, Inc. is HARTREE PARTNERS, LP, holding approximately 3.80 million shares — equal to 8.71% of outstanding shares — as of September 30, 2025.
A total of 175 institutional investors currently hold HDSN stock, with a combined institutional value of approximately $330,445,591 as of the most recent 13F filing period.
Frequently asked questions
HDSN ownershipHudson Technologies, Inc. (HDSN) is primarily owned by institutional investors, who hold approximately 79.1% of shares. The largest shareholder is HARTREE PARTNERS, LP with a 8.71% stake. Company insiders hold 21.45%. Data sourced from SEC Form 13F as of September 30, 2025.