Aldeyra Therapeutics, Inc.
Aldeyra Therapeutics, Inc. (ALDX) Stock Ownership
Institutional vs insider vs public ownership from 13F and float data — top holders, activity, and insider trades below.
SEC 13F · FMP · ALDX · as of Sep 30, 2025
Ownership Breakdown
139
Institutional Holders
▲ 10 vs Q2
$205.30M
Total Inst. Value
▲ $73.89M vs Q2
60.32M
Shares Outstanding
freeFloat 87.74%
39.34M
13F Shares Held
▲ 5.04M 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
ALDX largest shareholders · institutional ownership
Q3 2025 · SEC 13F
Showing top 10 holders
| Holder | Shares | % Owned | Weight | Value | Reported | Change |
|---|---|---|---|---|---|---|
KNOLL CAPITAL MANAGEMENT, LLC pharmaceutical preparations | 5.48M | 9.12% | 9.12% | $28.58B | Nov 14, 2025 | — held |
PERCEPTIVE ADVISORS LLC pharmaceutical preparations | 5.22M | 8.70% | 8.70% | $27.26B | Nov 14, 2025 | ▲ 1.17M |
BLACKROCK, INC. pharmaceutical preparations | 3.80M | 6.34% | 6.34% | $19.86B | Nov 12, 2025 | ▼ 47.2K |
VANGUARD GROUP INC pharmaceutical preparations | 3.59M | 5.98% | 5.98% | $18.75B | Nov 7, 2025 | ▲ 90.3K |
ARDSLEY ADVISORY PARTNERS LP pharmaceutical preparations | 1.90M | 3.16% | 3.16% | $9.92B | Nov 14, 2025 | ▼ 150.0K |
AQR CAPITAL MANAGEMENT LLC pharmaceutical preparations | 1.51M | 2.51% | 2.51% | $7.86B | Nov 14, 2025 | ▲ 31.5K |
D. E. SHAW & CO., INC. pharmaceutical preparations | 1.38M | 2.30% | 2.30% | $7.20B | Nov 14, 2025 | ▲ 892.2K |
KINGDON CAPITAL MANAGEMENT, L.L.C. pharmaceutical preparations | 1.33M | 2.22% | 2.22% | $6.95B | Nov 14, 2025 | — held |
GEODE CAPITAL MANAGEMENT, LLC pharmaceutical preparations | 1.18M | 1.96% | 1.96% | $6.14B | Nov 12, 2025 | ▲ 29.8K |
KENNEDY CAPITAL MANAGEMENT LLC pharmaceutical preparations | 1.11M | 1.85% | 1.85% | $5.81B | Nov 13, 2025 | ▲ 425.2K |
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
32
Increased
+5.85M shares2
New Positions
first time holders11
Decreased
−649.2K shares0
Sold Out
fully exitedNet shares change (top 50)
+5.20M
+5.85M / −649.2K
Net new holders
+23
2 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
ALDX 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.
1
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 |
|---|---|---|---|---|---|---|---|
Brady Todd C President and CEO | Jun 3, 2026 | Purchase | 250,000 | $1.67 | $418.4K | 1.72M | Form 4 ↗ |
Brady Todd C President and CEO | Mar 27, 2026 | Award | 1,880,510 | $1.77 | $3.33M | 1.88M | Form 4 ↗ |
Brady Todd C President and CEO | Mar 27, 2026 | Award | 632,318 | — | — | 632.3K | Form 4 ↗ |
DOUGLAS RICHARD director | Mar 19, 2026 | Purchase | 70,000 | $1.40 | $98.0K | 195.0K | Form 4 ↗ |
Alfieri Michael Principal Financial Officer | Mar 18, 2026 | Purchase | 5,000 | $1.42 | $7.1K | 7.5K | Form 4 ↗ |
Alfieri Michael Principal Financial Officer | Aug 13, 2025 | Purchase | 2,500 | $5.30 | $13.3K | 2.5K | Form 4 ↗ |
Machatha Stephen Chief Development Officer | Aug 11, 2025 | Sale | 22,073 | $5.15 | $113.7K | 221.8K | Form 4 ↗ |
Walker Neal director | Jun 10, 2025 | Award | 62,728 | $2.69 | $168.4K | 62.7K | Form 4 ↗ |
Walker Neal director | Jun 10, 2025 | Award | 2,413 | $2.69 | $6.5K | 2.4K | Form 4 ↗ |
Miller-Rich Nancy director | Jun 10, 2025 | Award | 62,728 | $2.69 | $168.4K | 62.7K | 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
Aldeyra Therapeutics, Inc. (ALDX) is primarily owned by institutional investors, who hold approximately 65.2% of total shares outstanding. Company insiders own approximately 12.26%, while retail and public investors account for the remaining 22.52%.
The largest institutional shareholder of Aldeyra Therapeutics, Inc. is KNOLL CAPITAL MANAGEMENT, LLC, holding approximately 5.48 million shares — equal to 9.12% of outstanding shares — as of September 30, 2025.
A total of 139 institutional investors currently hold ALDX stock, with a combined institutional value of approximately $205,303,062 as of the most recent 13F filing period.
Frequently asked questions
ALDX ownershipAldeyra Therapeutics, Inc. (ALDX) is primarily owned by institutional investors, who hold approximately 65.2% of shares. The largest shareholder is KNOLL CAPITAL MANAGEMENT, LLC with a 9.12% stake. Company insiders hold 12.26%. Data sourced from SEC Form 13F as of September 30, 2025.