Hydrofarm Holdings Group, Inc. (HYFM) Ownership
HYFM ownership summary
as of October 18, 2026- Institutions
- 13.0% of shares outstanding
- Insiders
- 22.42% of shares outstanding
- Shares outstanding
- 4.8M
- Float
- 3.6M shares available to trade
- Short interest
- 10.26% 438K shares short
- Days to cover
- 5.71 short interest up 0.0% vs prior month
- Institutions 12.98%
- Insiders 22.42%
- Other investors 64.60%
HYFM top institutional holders
20 largest| # | Holder | % of shares | Shares | Value | Change | Reported |
|---|---|---|---|---|---|---|
| 1 | Renaissance Technologies Corp | 1.46% | 70K | $54,602 | −1,800 (−2.5%) | June 30, 2026 |
| 2 | BlackRock Inc | 1.05% | 50K | $39,161 | — | June 30, 2026 |
| 3 | Vanguard Capital Management, LLC | 0.82% | 40K | $30,794 | — | June 30, 2026 |
| 4 | Geode Capital Management, LLC | 0.70% | 34K | $26,119 | −28,928 (−46.2%) | June 30, 2026 |
| 5 | Citadel Advisors Llc | 0.50% | 24K | $18,612 | +23,985 (0.0%) | June 30, 2026 |
| 6 | Vanguard Fiduciary Trust Co | 0.38% | 18K | $14,032 | — | June 30, 2026 |
| 7 | State Street Corp | 0.33% | 16K | $12,428 | — | June 30, 2026 |
| 8 | Virtu Financial LLC | 0.30% | 15K | $11,404 | +14,696 (0.0%) | June 30, 2026 |
| 9 | Compass Ion Advisors, LLC | 0.22% | 11K | $8,344 | +10,753 (0.0%) | June 30, 2026 |
| 10 | Susquehanna International Group, LLP | 0.22% | 11K | $8,236 | +10,613 (0.0%) | June 30, 2026 |
| 11 | Tower Research Capital LLC | 0.11% | 5,439 | $4,221 | +2,528 (+86.8%) | June 30, 2026 |
| 12 | UBS Group AG | 0.09% | 4,331 | $3,361 | +3,369 (+350.2%) | June 30, 2026 |
| 13 | Jnba Financial Advisors Inc | 0.04% | 2,000 | $1,552 | — | June 30, 2026 |
| 14 | Vanguard Global Advisers, LLC | 0.03% | 1,269 | $985 | — | June 30, 2026 |
| 15 | Advisor Group Holdings, Inc. | 0.01% | 503 | $390 | +282 (+127.6%) | June 30, 2026 |
| 16 | North Star Investment Management Corp | 0.01% | 370 | $287 | — | June 30, 2026 |
| 17 | Group One Trading, LLC | 0.01% | 338 | $262 | — | June 30, 2026 |
| 18 | BNP Paribas Arbitrage, SA | <0.01% | 198 | $154 | −30 (−13.2%) | June 30, 2026 |
| 19 | Hurley Capital, LLC | <0.01% | 103 | $80 | — | June 30, 2026 |
| 20 | Morgan Stanley - Brokerage Accounts | <0.01% | 90 | $70 | — | June 30, 2026 |
Value at the latest close. Change = shares bought or sold in the latest quarterly filing (13F). In the top 20, 7 holders added 66K shares and 3 cut 31K.
HYFM top mutual fund and ETF holders
6 largest| # | Holder | % of shares | Shares | Value | Change | Reported |
|---|---|---|---|---|---|---|
| 1 | Fidelity Extended Market Index | 0.57% | 27K | $21,255 | +9,524 (+53.3%) | August 31, 2026 |
| 2 | Fidelity Total Market Index | 0.17% | 8,299 | $6,440 | — | August 31, 2026 |
| 3 | Fidelity Series Total Market Index | 0.10% | 4,748 | $3,684 | — | August 31, 2026 |
| 4 | Amplify Seymour Cannabis ETF | 0.06% | 2,683 | $2,082 | — | September 30, 2026 |
| 5 | Vanguard U.S. Eq Idx £ Acc | 0.03% | 1,269 | $985 | — | August 31, 2026 |
| 6 | Guggenheim Active Allocation Fund | <0.01% | 92 | $71 | +46 (+100.0%) | May 31, 2026 |
Funds report holdings monthly or quarterly; dates differ by fund.
HYFM insider transactions
latest 1| Date | Name | Transaction | Price | Shares | Value |
|---|---|---|---|---|---|
| 2026-01-06 | Kevin Patrick O'brien | Sell | $1.51 | 1,150 | $1,736 |
Reported trades by company officers, directors and other filers (including disclosures by members of Congress where EODHD lists them). "—" where the filing gives no share count.
HYFM shares outstanding
Year-end shares outstanding, adjusted for splits.
Who owns HYFM
Institutional investors own 13.0% of Hydrofarm's shares and insiders 22.42%. The largest holder is Renaissance Technologies Corp with 1.46% of the shares (70K), as of June 30, 2026. Among the top 20 institutions, 7 added shares and 3 reduced their stake in the latest filings. Short interest is 10.26% of the float, or 5.71 days of average trading volume. The share count rose 133.3% since 2018.
Related: HYFM analyst forecast, HYFM key metrics. See the HYFM stock overview for the latest quote and news.
HYFM ownership FAQ
Who owns the most Hydrofarm stock?
The largest shareholders of Hydrofarm are Renaissance Technologies Corp (1.46%), BlackRock Inc (1.05%), Vanguard Capital Management, LLC (0.82%), Geode Capital Management, LLC (0.70%), Citadel Advisors Llc (0.50%).
What percentage of Hydrofarm is owned by institutions?
Institutions hold 13.0% of Hydrofarm's shares outstanding; insiders hold 22.42%.
Which funds own Hydrofarm?
The largest fund holders of Hydrofarm are Fidelity Extended Market Index (0.57%), Fidelity Total Market Index (0.17%), Fidelity Series Total Market Index (0.10%), Amplify Seymour Cannabis ETF (0.06%), Vanguard U.S. Eq Idx £ Acc (0.03%).
What is Hydrofarm's short interest?
438K shares of Hydrofarm were sold short, 10.26% of the float; at the average daily volume it would take 5.71 days to cover.
Are insiders buying or selling Hydrofarm?
Of the latest 1 reported insider transactions in Hydrofarm (since January 6, 2026), 0 were purchases and 1 were sales.
How many shares of Hydrofarm are outstanding?
Hydrofarm has 4.8M shares outstanding, of which 3.6M are in the public float.