Alto Neuroscience, Inc. (ANRO) Ownership
ANRO ownership summary
as of October 18, 2026- Institutions
- 87.1% of shares outstanding
- Insiders
- 4.21% of shares outstanding
- Shares outstanding
- 39.2M
- Float
- 29.6M shares available to trade
- Short interest
- 13.91% 4.7M shares short
- Days to cover
- 7.73 short interest up 21.5% vs prior month
- Institutions 87.12%
- Insiders 4.21%
- Other investors 8.67%
ANRO top institutional holders
20 largest| # | Holder | % of shares | Shares | Value | Change | Reported |
|---|---|---|---|---|---|---|
| 1 | Alpha Wave Global LP | 9.45% | 3.7M | $81.3M | — | June 30, 2026 |
| 2 | COMMODORE CAPITAL LP | 6.94% | 2.7M | $59.7M | — | June 30, 2026 |
| 3 | BlackRock Inc | 5.40% | 2.1M | $46.5M | +1.5M (+218.4%) | June 30, 2026 |
| 4 | Perceptive Advisors LLC | 4.10% | 1.6M | $35.3M | −400,000 (−19.9%) | June 30, 2026 |
| 5 | Adage Capital Partners Gp LLC | 4.08% | 1.6M | $35.1M | +1.2M (+315.6%) | June 30, 2026 |
| 6 | Vanguard Capital Management, LLC | 3.54% | 1.4M | $30.5M | +182,452 (+15.1%) | June 30, 2026 |
| 7 | Spruce Street Capital LP | 3.45% | 1.4M | $29.7M | +27,837 (+2.1%) | June 30, 2026 |
| 8 | Vivo Capital, LLC | 3.08% | 1.2M | $26.5M | +173,307 (+16.7%) | June 30, 2026 |
| 9 | Franklin Templeton Inc | 2.58% | 1.0M | $22.2M | −88,567 (−8.0%) | June 30, 2026 |
| 10 | Armistice Capital, LLC | 2.20% | 864K | $19.0M | −48,000 (−5.3%) | June 30, 2026 |
| 11 | Affinity Asset Advisors, LLC | 2.17% | 850K | $18.6M | +350,000 (+70.0%) | June 30, 2026 |
| 12 | Vestal Point Capital LP | 2.00% | 785K | $17.2M | −1.3M (−62.0%) | June 30, 2026 |
| 13 | State Street Corp | 1.75% | 686K | $15.0M | +486,442 (+243.8%) | June 30, 2026 |
| 14 | Geode Capital Management, LLC | 1.73% | 678K | $14.9M | +385,300 (+131.5%) | June 30, 2026 |
| 15 | 72 Investment Holdings, LLC | 1.70% | 668K | $14.7M | — | June 30, 2026 |
| 16 | Northern Trust Corp | 1.61% | 633K | $13.9M | +159,298 (+33.6%) | June 30, 2026 |
| 17 | Millennium Management LLC | 1.42% | 558K | $12.2M | −263,662 (−32.1%) | June 30, 2026 |
| 18 | Point72 Asset Management, L.P. | 1.28% | 503K | $11.0M | −137 (−0.0%) | June 30, 2026 |
| 19 | VR Adviser, LLC | 1.27% | 500K | $11.0M | — | June 30, 2026 |
| 20 | Integral Health Asset Management, LLC | 1.27% | 500K | $11.0M | — | June 30, 2026 |
Value at the latest close. Change = shares bought or sold in the latest quarterly filing (13F). In the top 20, 9 holders added 4.4M shares and 6 cut 2.1M.
ANRO top mutual fund and ETF holders
20 largest| # | Holder | % of shares | Shares | Value | Change | Reported |
|---|---|---|---|---|---|---|
| 1 | Vanguard MStar Total Stk Mkt Idx Invest | 2.58% | 1.0M | $22.2M | — | August 31, 2026 |
| 2 | iShares Russell 2000 ETF | 2.13% | 837K | $18.4M | +2,203 (+0.3%) | September 30, 2026 |
| 3 | Franklin Biotechnology Discv A(acc)USD | 1.65% | 646K | $14.2M | — | August 31, 2026 |
| 4 | Franklin Biotechnology Discovery A | 0.89% | 348K | $7.6M | — | August 31, 2026 |
| 5 | iShares Russell 2000 Growth ETF | 0.76% | 298K | $6.5M | −378 (−0.1%) | September 30, 2026 |
| 6 | Fidelity Small Cap Index | 0.73% | 287K | $6.3M | +2,900 (+1.0%) | July 31, 2026 |
| 7 | iShares Biotechnology ETF | 0.71% | 279K | $6.1M | −2,120 (−0.8%) | September 30, 2026 |
| 8 | Heptagon Driehaus US Micro Cap Eq C$ Acc | 0.67% | 264K | $5.8M | +67,917 (+34.6%) | August 31, 2026 |
| 9 | Biotech Growth Ord | 0.66% | 258K | $5.7M | — | June 30, 2026 |
| 10 | State Street® SPDR® S&P® PhrmctlsETF | 0.64% | 253K | $5.5M | −3,140 (−1.2%) | September 30, 2026 |
| 11 | T. Rowe Price New Horizons | 0.64% | 250K | $5.5M | −10,214 (−3.9%) | August 31, 2026 |
| 12 | Schwab US Small-Cap ETF™ | 0.53% | 208K | $4.6M | +135 (+0.1%) | September 30, 2026 |
| 13 | Vanguard Russell 2000 ETF | 0.38% | 151K | $3.3M | +3,695 (+2.5%) | August 31, 2026 |
| 14 | Fidelity Extended Market Index | 0.37% | 147K | $3.2M | −2,116 (−1.4%) | August 31, 2026 |
| 15 | T. Rowe Price Integrated US Sm Gr Eq | 0.36% | 142K | $3.1M | — | August 31, 2026 |
| 16 | iShares Micro-Cap ETF | 0.26% | 101K | $2.2M | −695 (−0.7%) | September 30, 2026 |
| 17 | AdvisorShares Psychedelics ETF | 0.21% | 82K | $1.8M | — | September 30, 2026 |
| 18 | Driehaus Micro Cap Growth USD | 0.20% | 78K | $1.7M | +78,491 (0.0%) | July 31, 2026 |
| 19 | Schwab Small Cap Index | 0.16% | 64K | $1.4M | — | August 31, 2026 |
| 20 | Fidelity Total Market Index | 0.15% | 59K | $1.3M | −2,105 (−3.5%) | August 31, 2026 |
Funds report holdings monthly or quarterly; dates differ by fund.
ANRO insider transactions
latest 3| Date | Name | Transaction | Price | Shares | Value |
|---|---|---|---|---|---|
| 2024-07-09 | Adam Savitz | Buy | $12.60 | 12,069 | $152,069 |
| 2024-03-28 | Nicholas Conrad Smith | Buy | $16.36 | 6,150 | $100,614 |
| 2024-02-06 | Wave Global Lp Alpha | Buy | $16.00 | 600,000 | $9.6M |
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.
ANRO shares outstanding
Year-end shares outstanding, adjusted for splits.
Who owns ANRO
Institutional investors own 87.1% of Alto Neuroscience's shares and insiders 4.21%. The largest holder is Alpha Wave Global LP with 9.45% of the shares (3.7M), as of June 30, 2026. Among the top 20 institutions, 9 added shares and 6 reduced their stake in the latest filings. Short interest is 13.91% of the float, or 7.73 days of average trading volume. The share count rose 1,496.2% since 2021.
Related: ANRO analyst forecast, ANRO key metrics. See the ANRO stock overview for the latest quote and news.
ANRO ownership FAQ
Who owns the most Alto Neuroscience stock?
The largest shareholders of Alto Neuroscience are Alpha Wave Global LP (9.45%), COMMODORE CAPITAL LP (6.94%), BlackRock Inc (5.40%), Perceptive Advisors LLC (4.10%), Adage Capital Partners Gp LLC (4.08%).
What percentage of Alto Neuroscience is owned by institutions?
Institutions hold 87.1% of Alto Neuroscience's shares outstanding; insiders hold 4.21%.
Which funds own Alto Neuroscience?
The largest fund holders of Alto Neuroscience are Vanguard MStar Total Stk Mkt Idx Invest (2.58%), iShares Russell 2000 ETF (2.13%), Franklin Biotechnology Discv A(acc)USD (1.65%), Franklin Biotechnology Discovery A (0.89%), iShares Russell 2000 Growth ETF (0.76%).
What is Alto Neuroscience's short interest?
4.7M shares of Alto Neuroscience were sold short, 13.91% of the float; at the average daily volume it would take 7.73 days to cover.
Are insiders buying or selling Alto Neuroscience?
Of the latest 3 reported insider transactions in Alto Neuroscience (since February 6, 2024), 3 were purchases and 0 were sales.
How many shares of Alto Neuroscience are outstanding?
Alto Neuroscience has 39.2M shares outstanding, of which 29.6M are in the public float.