Septerna, Inc.
Ownership
Ownership Structure
Who owns Septerna, Inc. (SEPN)? This page shows the largest institutions and funds, the ownership structure and the latest insider transactions. 56.6% of the shares are freely tradable; institutional investors hold 102.7%.
Largest Shareholders
Institutions
| Name | Stake (%) | Shares | Change (%) | Date |
|---|---|---|---|---|
| RA Capital Management, LLC | 14.99 | 6,995,858 | +0.0 | 03/31/2026 |
| TRV GP V, LLC | 13.32 | 6,215,591 | +0.0 | 06/30/2026 |
| Driehaus Capital Management LLC | 9.42 | 4,395,572 | -8.6 | 03/31/2026 |
| TRV GP VI, LLC | 9.02 | 4,211,659 | +0.0 | 06/30/2026 |
| Samsara BioCapital, LLC | 6.75 | 3,149,128 | +0.0 | 06/30/2026 |
| The Goldman Sachs Group Inc | 6.23 | 2,906,427 | +7.0 | 03/31/2026 |
| Siren, L.L.C. | 4.28 | 2,000,000 | +0.0 | 03/31/2026 |
| BlackRock Inc | 3.90 | 1,822,174 | +1.2 | 03/31/2026 |
| Bvf Inc | 2.90 | 1,353,249 | -21.4 | 03/31/2026 |
| venBio Select Advisor LLC | 2.87 | 1,337,500 | +0.0 | 03/31/2026 |
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 |
|---|---|---|---|---|---|
| Third Rock Ventures V, L.P. | 10% Owner | 6,068,391 | 239,701,445 $ | Aug 12, 2026 | direct |
| Ra Capital Management, L.p. | Director | 725,443 | 28,654,999 $ | Aug 12, 2026 | indirect |
| Bhatt Elizabeth | President and COO | 174,209 | 6,881,256 $ | Aug 11, 2026 | direct |
| Long Daniel D. | SVP, Drug Discovery | 96,412 | 3,808,274 $ | Sep 1, 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 |
|---|---|---|---|---|---|---|
| Sep 1, 2026 | Long Daniel D. | SVP, Drug Discovery | Sell | 3,333 | 37.83 | 126,078 |
| Sep 1, 2026 | Long Daniel D. | SVP, Drug Discovery | Other | 3,333 | 2.76 | 9,199 |
| Aug 12, 2026 | Ra Capital Management, L.p. | Director | Sell | 746,500 | 42.50 | 31,726,250 |
| Aug 12, 2026 | Third Rock Ventures V, L.P. | 10% Owner | Sell | 141 | 51.08 | 7,202 |
| Aug 12, 2026 | Third Rock Ventures V, L.P. | 10% Owner | Sell | 147,059 | 50.27 | 7,392,656 |
| Aug 11, 2026 | Bhatt Elizabeth | President and COO | Sell | 25,000 | 44.00 | 1,100,000 |
| Aug 11, 2026 | Bhatt Elizabeth | President and COO | Other | 6,319 | 2.76 | 17,440 |
| Aug 11, 2026 | Bhatt Elizabeth | President and COO | Other | 18,681 | 6.81 | 127,218 |
| Aug 3, 2026 | Long Daniel D. | SVP, Drug Discovery | Sell | 2,334 | 34.68 | 80,944 |
| Aug 3, 2026 | Long Daniel D. | SVP, Drug Discovery | Sell | 1,000 | 33.98 | 33,976 |
| Aug 3, 2026 | Long Daniel D. | SVP, Drug Discovery | Other | 1,518 | 2.76 | 4,190 |
| Aug 3, 2026 | Long Daniel D. | SVP, Drug Discovery | Other | 1,816 | 2.76 | 5,012 |
| Jul 15, 2026 | Bhatt Elizabeth | President and COO | Sell | 4,000 | 33.99 | 135,974 |
| Jul 15, 2026 | Bhatt Elizabeth | President and COO | Other | 4,000 | 6.81 | 27,240 |
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.