Ranked by reported Q1 2026 13F market value
Share of total reported institutional value in ALDX held by the largest 10 / 25 filers.
| # | Institution | Shares Held | Market Value | QoQ Change | Ownership % | % of Fund |
|---|---|---|---|---|---|---|
| 1 | Knoll Capital Management, LLC | 5.5M | $9.3M | 0.0% | 9.077% | 5.14% |
| 2 | BlackRock, Inc. | 3.8M | $6.4M | -2.2% | 6.240% | 0.00% |
| 3 | AQR CAPITAL MANAGEMENT LLC | 2.8M | $4.8M | +130.7% | 4.691% | 0.00% |
| 4 | VANGUARD CAPITAL MANAGEMENT LLC | 2.4M | $4.0M | β | 3.919% | 0.00% |
| 5 | KINGDON CAPITAL MANAGEMENT, L.L.C. | 2.2M | $3.6M | +16.3% | 3.568% | 0.59% |
| 6 | 683 Capital Management, LLC | 1.5M | $2.5M | -2.0% | 2.487% | 0.20% |
| 7 | D. E. Shaw & Co., Inc. | 1.4M | $2.4M | -12.3% | 2.328% | 0.00% |
| 8 | GEODE CAPITAL MANAGEMENT, LLC | 1.3M | $2.1M | +6.9% | 2.075% | 0.00% |
| 9 | ARDSLEY ADVISORY PARTNERS LP | 1.3M | $2.1M | -16.7% | 2.072% | 0.29% |
| 10 | STATE STREET CORP | 1.1M | $1.9M | +2.4% | 1.864% | 0.00% |
| 11 | MILLENNIUM MANAGEMENT LLC | 995K | $1.7M | +2158.9% | 1.650% | 0.00% |
| 12 | RENAISSANCE TECHNOLOGIES LLC | 863K | $1.5M | +146.6% | 1.431% | 0.00% |
| 13 | VANGUARD PORTFOLIO MANAGEMENT LLC | 808K | $1.4M | β | 1.339% | 0.00% |
| 14 | JACOBS LEVY EQUITY MANAGEMENT, INC | 797K | $1.3M | -17.8% | 1.321% | 0.01% |
| 15 | Propel Bio Management, LLC | 731K | $1.2M | β | 1.211% | 0.78% |
| 16 | DIMENSIONAL FUND ADVISORS LP | 624K | $1.1M | +1.9% | 1.035% | 0.00% |
| 17 | SUSQUEHANNA INTERNATIONAL GROUP, LLP | 622K | $1.1M | +66.5% | 1.032% | 0.00% |
| 18 | GOLDMAN SACHS GROUP INC | 543K | $918K | +77.7% | 0.900% | 0.00% |
| 19 | UBS Group AG | 538K | $908K | +461.9% | 0.891% | 0.00% |
| 20 | MORGAN STANLEY | 519K | $877K | -21.1% | 0.860% | 0.00% |
| 21 | NORTHERN TRUST CORP | 375K | $633K | -1.2% | 0.621% | 0.00% |
| 22 | VANGUARD FIDUCIARY TRUST CO | 339K | $572K | β | 0.561% | 0.00% |
| 23 | WOODSTOCK CORP | 267K | $451K | 0.0% | 0.442% | 0.04% |
| 24 | IEQ CAPITAL, LLC | 267K | $450K | +84.8% | 0.442% | 0.00% |
| 25 | TWO SIGMA INVESTMENTS, LP | 224K | $378K | -22.2% | 0.371% | 0.00% |
denotes a marquee investor (Buffett, Burry, ARK, Tiger Global, Pershing Square, Baupost and other widely-followed managers). β% of Fundβ shows how much of that investorβs total 13F portfolio is invested in ALDX β a direct measure of their conviction.
Filings activity in ALDX during Q1 2026, grouped by how each filer changed its position.
Institutions that opened a new ALDX position in Q1 2026
Institutions that fully closed their ALDX position in Q1 2026
8 quarters of 13F filings Β· Ξ columns show change vs prior quarter
| Quarter | Inst. Holders | Ξ Holders | Ownership % | Ξ Ownership | Total 13F Value | Ξ Value |
|---|---|---|---|---|---|---|
| Q1 2026 | 120 | 10% | 56.15% | 129.91 pp | $60M | 70% |
| Q4 2025 | 134 | +3.9% | 186.06% | 2.25 pp | $198M | 1.2% |
| Q3 2025 | 129 | +6.6% | 188.31% | +66.70 pp | $200M | +55% |
| Q2 2025 | 121 | 1.6% | 121.61% | 78.38 pp | $129M | 40% |
| Q1 2025 | 123 | +7.0% | 199.99% | +26.41 pp | $214M | +16% |
| Q4 2024 | 115 | +3.6% | 173.58% | 9.06 pp | $184M | 5.0% |
| Q3 2024 | 111 | +7.8% | 182.64% | +36.06 pp | $194M | +25% |
| Q2 2024 | 103 | β | 146.58% | β | $156M | β |
Source: SEC 13F institutional filings. Ownership % requires market cap data and will show once linked. Ξ columns compare to the immediately prior filed quarter.
Quick answers to the most common questions about buying ALDX stock.
Based on Q1 2026 13F filings, institutional ownership of Aldeyra Therapeutics, Inc. stands at 56.1%, held across 120 reporting institutions.
Knoll Capital Management, LLC is the largest reported institutional holder of ALDX, with approximately 5,475,516 shares worth $0.01B as of Q1 2026.
Yes β 4 widely-followed marquee investors appear among the top 25 institutional holders of ALDX, including MILLENNIUM MANAGEMENT LLC, RENAISSANCE TECHNOLOGIES LLC, SUSQUEHANNA INTERNATIONAL GROUP, LLP, TWO SIGMA INVESTMENTS, LP.
Our composite Smart Money Score for ALDX is 43 out of 100 (Neutral). It combines net institutional buying activity, ownership shift, marquee investor presence, and holder-count growth.
20 institutions opened new positions in ALDX during Q1 2026, while 34 fully exited. 15 added to existing positions and 85 trimmed.
ALDX institutional ownership fell by 129.91 percentage points quarter-over-quarter, with a net change of -14 holders.
The top 10 institutions account for 65.5% of all reported 13F value in ALDX, and the top 25 account for 89.7%.
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.
Aldeyra Therapeutics, Inc. (ALDX) Institutional Ownership