Who owns Aldeyra Therapeutics (ALDX)
Which tracked institutional funds hold ALDX, how they are positioned, and who is buying versus exiting — from SEC Form 13F-HR filings. See ALDX company fundamentals →
Ownership as of the 2026-Q2 13F filings (latest filed 2026-09-22). 13F is disclosed up to 45 days after quarter-end, so the most recent quarter fills in over the following weeks.
How the tape is positioned
18 tracked funds added or opened ALDX while 10 trimmed or exited it between 2026-Q1 and 2026-Q2 — the tape is split. When large holders disagree on a name, the funds moving first are sometimes ahead of the story.
A prompt to read the filings, not a verdict. 13F is a quarter-end snapshot disclosed up to 45 days late; a fund adds or exits for mandate, benchmark, and timing reasons that have nothing to do with a view on the stock. This is a starting question, not a signal to trade.
Conviction spread
ALDX’s largest tracked holder by dollar value, Knoll Capital Management, LLC, sizes it at 6.5% of its own reported 13F book, while the median holder sizes it at 0.0% of theirs — a 6.5pp conviction gap — its largest holder concentrates the name more heavily than the typical one.
Book-share is each fund’s reported value in ALDX divided by its whole reported 13F book, so it is comparable across funds of different sizes and is unaffected by stock splits. A higher share means a fund has committed more of its book to the name — a starting question about conviction, not a verdict or a signal to trade.
Institutional & insider positioning
Between 2026-Q1 and 2026-Q2, across 103 tracked filers holding ALDX, 48 increased or opened the position and 83 reduced or closed it; over the same quarter, open-market insider Form 4s were net purchases.
This fuses two public signals for the same quarter — how tracked institutions changed their positions and whether insiders bought or sold in the open market. It describes what was filed; it is a starting question, not a verdict or a signal to trade.
New buyers & exits
Funds opening or closing a position in ALDX between the 2026-Q1 and 2026-Q2 13F filings, and the largest changes among funds holding it in both. New buyers and exits are counted on fund presence (split-invariant); adds and trims are measured on reported value.
New buyers 1
- ARROWSTREET CAPITAL, LIMITED PARTNERSHIP$897K
Full exits 2
- ACADIAN ASSET MANAGEMENT LLC$1M
- Propel Bio Management, LLC$1M
Largest adds
- AQR CAPITAL MANAGEMENT LLC$3M
- MARSHALL WACE, LLP$3M
- Knoll Capital Management, LLC$2M
- Qube Research & Technologies Ltd$2M
- KINGDON CAPITAL MANAGEMENT, L.L.C.$2M
- D. E. Shaw & Co., Inc.$2M
Largest trims
- BlackRock, Inc.$4M
- STATE STREET CORP$1M
- MILLENNIUM MANAGEMENT LLC$914K
- GEODE CAPITAL MANAGEMENT, LLC$846K
- NORTHERN TRUST CORP$402K
- SUSQUEHANNA INTERNATIONAL GROUP, LLP$346K
Institutional holders
One row per tracked fund, most shares held first (every row is from one quarter; reported value breaks ties). “% of value” is the fund’s share of this security’s tracked institutional value — not of shares outstanding.
| Fund | Shares | Reported value | % of value | Quarter |
|---|---|---|---|---|
| Knoll Capital Management, LLC | 5,475,516 | $12M | 15.7% | 2026-Q2 |
| AQR CAPITAL MANAGEMENT LLC added | 3,751,558 | $8M | 10.7% | 2026-Q2 |
| KINGDON CAPITAL MANAGEMENT, L.L.C. added | 2,652,315 | $6M | 7.6% | 2026-Q2 |
| VANGUARD CAPITAL MANAGEMENT LLC trimmed | 2,361,796 | $5M | 6.8% | 2026-Q2 |
| D. E. Shaw & Co., Inc. added | 1,940,338 | $4M | 5.6% | 2026-Q2 |
| MARSHALL WACE, LLP added | 1,506,974 | $3M | 4.3% | 2026-Q2 |
| 683 Capital Management, LLC trimmed | 1,450,000 | $3M | 4.2% | 2026-Q2 |
| JANE STREET GROUP, LLC added | 1,375,115 | $3M | 3.9% | 2026-Q2 |
| BlackRock, Inc. trimmed | 1,257,243 | $3M | 3.6% | 2026-Q2 |
| Qube Research & Technologies Ltd added | 1,128,803 | $2M | 3.2% | 2026-Q2 |
| ARDSLEY ADVISORY PARTNERS LP added | 975,000 | $2M | 2.8% | 2026-Q2 |
| RENAISSANCE TECHNOLOGIES LLC added | 882,000 | $2M | 2.5% | 2026-Q2 |
| VANGUARD PORTFOLIO MANAGEMENT LLC trimmed | 794,863 | $2M | 2.3% | 2026-Q2 |
| GOLDMAN SACHS GROUP INC added | 725,444 | $2M | 2.1% | 2026-Q2 |
| JACOBS LEVY EQUITY MANAGEMENT, INC trimmed | 646,840 | $1M | 1.9% | 2026-Q2 |
| MORGAN STANLEY added | 608,321 | $1M | 1.7% | 2026-Q2 |
| GEODE CAPITAL MANAGEMENT, LLC trimmed | 596,029 | $1M | 1.7% | 2026-Q2 |
| DIMENSIONAL FUND ADVISORS LP trimmed | 529,083 | $1M | 1.5% | 2026-Q2 |
| ARROWSTREET CAPITAL, LIMITED PARTNERSHIP new | 421,178 | $897K | 1.2% | 2026-Q2 |
| CITADEL ADVISORS LLC added | 379,144 | $808K | 1.1% | 2026-Q2 |
| MILLENNIUM MANAGEMENT LLC trimmed | 360,350 | $768K | 1.0% | 2026-Q2 |
| UBS Group AG trimmed | 301,940 | $643K | 0.9% | 2026-Q2 |
| VANGUARD FIDUCIARY TRUST CO trimmed | 298,242 | $635K | 0.9% | 2026-Q2 |
| XTX Topco Ltd added | 254,777 | $543K | 0.7% | 2026-Q2 |
| WOODSTOCK CORP trimmed | 242,756 | $517K | 0.7% | 2026-Q2 |
| STATE STREET CORP trimmed | 233,774 | $498K | 0.7% | 2026-Q2 |
| IEQ CAPITAL, LLC trimmed | 206,593 | $440K | 0.6% | 2026-Q2 |
| CANTOR FITZGERALD, L. P. new | 200,000 | $426K | 0.6% | 2026-Q2 |
| Caption Management, LLC | 165,000 | $351K | 0.5% | 2026-Q2 |
| WELLS FARGO & COMPANY/MN trimmed | 162,336 | $346K | 0.5% | 2026-Q2 |
| Invesco Ltd. trimmed | 159,540 | $340K | 0.5% | 2026-Q2 |
| BNP PARIBAS FINANCIAL MARKETS added | 157,248 | $335K | 0.5% | 2026-Q2 |
| Palo Alto Investors LP | 155,709 | $332K | 0.4% | 2026-Q2 |
| Point72 Asset Management, L.P. added | 154,408 | $329K | 0.4% | 2026-Q2 |
| Connor, Clark & Lunn Investment Management Ltd. added | 154,292 | $329K | 0.4% | 2026-Q2 |
| Man Group plc new | 152,713 | $325K | 0.4% | 2026-Q2 |
| Jain Global LLC new | 131,502 | $280K | 0.4% | 2026-Q2 |
| TWO SIGMA INVESTMENTS, LP trimmed | 127,849 | $272K | 0.4% | 2026-Q2 |
| JPMORGAN CHASE & CO added | 109,578 | $225K | 0.3% | 2026-Q2 |
| NORTHERN TRUST CORP trimmed | 108,888 | $232K | 0.3% | 2026-Q2 |
| KENNEDY CAPITAL MANAGEMENT LLC added | 97,726 | $208K | 0.3% | 2026-Q2 |
| CANADA PENSION PLAN INVESTMENT BOARD added | 94,300 | $201K | 0.3% | 2026-Q2 |
| Squarepoint Ops LLC new | 94,048 | $200K | 0.3% | 2026-Q2 |
| Russell Investments Group, Ltd. added | 90,353 | $192K | 0.3% | 2026-Q2 |
| Mariner, LLC trimmed | 90,339 | $192K | 0.3% | 2026-Q2 |
| Chicago Partners Investment Group LLC added | 83,984 | $130K | 0.2% | 2026-Q2 |
| ROYAL BANK OF CANADA added | 79,783 | $170K | 0.2% | 2026-Q2 |
| Cerity Partners LLC trimmed | 72,712 | $155K | 0.2% | 2026-Q2 |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP trimmed | 58,398 | $124K | 0.2% | 2026-Q2 |
| CAPTRUST FINANCIAL ADVISORS trimmed | 51,778 | $110K | 0.1% | 2026-Q2 |
| WEALTH ENHANCEMENT ADVISORY SERVICES, LLC trimmed | 47,518 | $98K | 0.1% | 2026-Q2 |
| Quadrature Capital Ltd added | 46,044 | $98K | 0.1% | 2026-Q2 |
| Graham Capital Management, L.P. trimmed | 43,556 | $93K | 0.1% | 2026-Q2 |
| Creative Planning added | 38,200 | $81K | 0.1% | 2026-Q2 |
| AlphaCentric Advisors LLC added | 37,656 | $80K | 0.1% | 2026-Q2 |
| MERCER GLOBAL ADVISORS INC /ADV trimmed | 36,901 | $79K | 0.1% | 2026-Q2 |
| INTERNATIONAL ASSETS INVESTMENT MANAGEMENT, LLC trimmed | 36,750 | $89K | 0.1% | 2026-Q2 |
| PRICE T ROWE ASSOCIATES INC /MD/ trimmed | 35,091 | $75K | 0.1% | 2026-Q2 |
| BANK OF AMERICA CORP /DE/ trimmed | 33,925 | $72K | 0.1% | 2026-Q2 |
| TWO SIGMA SECURITIES, LLC added | 32,818 | $70K | 0.1% | 2026-Q2 |
| SIMPLEX TRADING, LLC trimmed | 28,957 | $62K | 0.1% | 2026-Q2 |
| Arax Advisory Partners added | 28,634 | $61K | 0.1% | 2026-Q2 |
| STATE OF WISCONSIN INVESTMENT BOARD trimmed | 28,400 | $60K | 0.1% | 2026-Q2 |
| RHUMBLINE ADVISERS trimmed | 26,652 | $57K | 0.1% | 2026-Q2 |
| Providence Wealth Advisors, LLC | 25,000 | $59K | 0.1% | 2026-Q2 |
| Schonfeld Strategic Advisors LLC new | 20,920 | $45K | 0.1% | 2026-Q2 |
| SEI INVESTMENTS CO trimmed | 20,739 | $44K | 0.1% | 2026-Q2 |
| StoneX Group Inc. new | 19,296 | $33K | 0.0% | 2026-Q2 |
| Federation des caisses Desjardins du Quebec | 18,106 | $39K | 0.1% | 2026-Q2 |
| FMR LLC added | 17,889 | $38K | 0.1% | 2026-Q2 |
| Vanguard Global Advisers, LLC | 17,687 | $38K | 0.1% | 2026-Q2 |
| LETKO, BROSSEAU & ASSOCIATES INC | 17,300 | $37K | 0.0% | 2026-Q2 |
| Y-Intercept (Hong Kong) Ltd trimmed | 17,084 | $36K | 0.0% | 2026-Q2 |
| Merit Financial Group, LLC trimmed | 16,664 | $35K | 0.0% | 2026-Q2 |
| BRIGHTON JONES LLC trimmed | 16,144 | $34K | 0.0% | 2026-Q2 |
| Activest Wealth Management added | 15,000 | $32K | 0.0% | 2026-Q2 |
| Cetera Investment Advisers trimmed | 14,699 | $31K | 0.0% | 2026-Q2 |
| Focus Partners Wealth trimmed | 13,863 | $30K | 0.0% | 2026-Q2 |
| LPL Financial LLC trimmed | 13,316 | $28K | 0.0% | 2026-Q2 |
| Caitong International Asset Management Co., Ltd added | 10,863 | $23K | 0.0% | 2026-Q2 |
| INSPIRION WEALTH ADVISORS, LLC | 10,000 | $24K | 0.0% | 2026-Q2 |
| Global Retirement Partners, LLC | 10,000 | $21K | 0.0% | 2026-Q2 |
| Integrated Wealth Concepts LLC trimmed | 8,765 | $19K | 0.0% | 2026-Q2 |
| BARCLAYS PLC trimmed | 5,769 | $12K | 0.0% | 2026-Q2 |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC | 4,825 | $10K | 0.0% | 2026-Q2 |
| Farther Finance Advisors, LLC added | 4,497 | $10K | 0.0% | 2026-Q2 |
| EverSource Wealth Advisors, LLC added | 4,027 | $9K | 0.0% | 2026-Q2 |
| Optiver Holding B.V. trimmed | 4,022 | $9K | 0.0% | 2026-Q2 |
| Essential Partners LLC trimmed | 2,070 | $4K | 0.0% | 2026-Q2 |
| RAFFA WEALTH MANAGEMENT, LLC | 1,897 | $4K | 0.0% | 2026-Q2 |
| Allworth Financial LP trimmed | 1,827 | $4K | 0.0% | 2026-Q2 |
| PNC Financial Services Group, Inc. added | 1,575 | $3K | 0.0% | 2026-Q2 |
| SBI Securities Co., Ltd. added | 1,423 | $3K | 0.0% | 2026-Q2 |
| IFP Advisors, Inc trimmed | 1,407 | $3K | 0.0% | 2026-Q2 |
| ROTHSCHILD INVESTMENT LLC trimmed | 355 | $756 | 0.0% | 2026-Q2 |
| CITIGROUP INC trimmed | 327 | $697 | 0.0% | 2026-Q2 |
| GAMMA Investing LLC trimmed | 320 | $682 | 0.0% | 2026-Q2 |
| True Wealth Design, LLC added | 312 | $665 | 0.0% | 2026-Q2 |
| Truvestments Capital LLC | 265 | $564 | 0.0% | 2026-Q2 |
| SJS Investment Consulting Inc. trimmed | 190 | $405 | 0.0% | 2026-Q2 |
Ownership over time
Tracked institutional holder count and total shares held by filing quarter (independent scales). The curated-era tail and any mid-ingest latest quarter are handled honestly — a partial quarter is not drawn as a collapse.
Reading this table
Funds hold the same stock for different reasons — an index fund “holds” almost everything, an active manager sizes a name to a mandate and a benchmark, and each fund entered at its own price and time. Because 13F is filed up to 45 days after quarter-end, every row is a backward-looking snapshot; a manager may have traded since. Share-class siblings (a company’s A and C shares) are rolled up to one line so a dual-class name is never double-counted. Compare like-for-like. A large holder is not an endorsement, and a fund exiting is not a warning — this is a starting question, not a verdict.
About 13F filings
A Form 13F is a quarterly disclosure that institutional investment managers with over $100 million in US-listed equities must file with the SEC. In plain English: it is a snapshot of the long stock positions a fund held at the end of a quarter. It covers long US-listed equities only — not short positions, options, cash, or private holdings — and the funds shown are the large sample we track, not the complete 13F universe.