Altimmune Inc
Ownership
Ownership Structure
Who owns Altimmune Inc (ALT)? This page shows the largest institutions and funds, the ownership structure and the latest insider transactions. 84.5% of the shares are freely tradable; institutional investors hold 57.8%.
Largest Shareholders
Institutions
| Name | Stake (%) | Shares | Change (%) | Date |
|---|---|---|---|---|
| Deep Track Capital, LP | 9.90 | 19,250,000 | +0.0 | 06/30/2026 |
| BlackRock Inc | 6.58 | 12,795,277 | +31.9 | 03/31/2026 |
| TCG Crossover Management, LLC | 5.14 | 10,000,000 | +0.0 | 06/30/2026 |
| State Street Corp | 3.67 | 7,145,550 | +39.6 | 03/31/2026 |
| Vanguard Capital Management, LLC | 2.91 | 5,658,049 | +0.0 | 03/31/2026 |
| Vanguard Portfolio Management, LLC | 2.77 | 5,382,002 | +0.0 | 03/31/2026 |
| Marshall Wace Asset Management Ltd | 2.07 | 4,017,901 | +335.4 | 03/31/2026 |
Funds
| Name | Stake (%) | Shares | Change (%) | Date |
|---|---|---|---|---|
| State Street® SPDR® S&P® Biotech ETF | 4.39 | 8,544,585 | -1.1 | 08/31/2026 |
| Vanguard MStar Total Stk Mkt Idx Invest | 2.96 | 5,748,771 | +0.0 | 07/31/2026 |
| iShares Russell 2000 ETF | 2.61 | 5,084,328 | -0.6 | 08/31/2026 |
Largest reported positions according to regulatory filings; stake as a percentage of shares outstanding, change versus the previous filing. Source: fundamentals data.
Insider holdings
| Person | Role | Shares | Value | As of | Type |
|---|---|---|---|---|---|
| Roberts M Scot | Chief Scientific Officer | 113,699 | 363,837 $ | Jul 31, 2026 | direct |
| Durso Jerome Benedict | President and CEO | 62,500 | 200,000 $ | Aug 13, 2026 | direct |
| Weaver Gregory L | Chief Financial Officer | 39,831 | 127,459 $ | Jul 31, 2026 | direct |
Holdings as of each person's most recent SEC Form 4 filing — excluding options and RSUs, which are not shares yet. Holdings may have changed between two filings.
Insiders
Insider Transactions
| Date | Person | Role | Type | Shares | Price | Value |
|---|---|---|---|---|---|---|
| Aug 13, 2026 | Durso Jerome Benedict | President and CEO | Buy | 15,000 | 2.95 | 44,250 |
| Jul 31, 2026 | Roberts M Scot | Chief Scientific Officer | Other | 875 | 2.41 | 2,112 |
| Jul 31, 2026 | Weaver Gregory L | Chief Financial Officer | Other | 1,753 | 2.41 | 4,232 |
Reportable transactions by officers and major shareholders from SEC Form 4 filings. "Other" includes things like stock grants and option exercises without a buy/sell character. View all insider transactions →
Data as of: September 17, 2026 · Source: fundamental data & SEC filings (annual and quarterly reports, 10-K/10-Q)
Note: pure fact-based analysis, not investment advice and not a solicitation to buy or sell. All figures without guarantee.