Who owns Septerna (SEPN)
Which tracked institutional funds hold SEPN, how they are positioned, and who is buying versus exiting — from SEC Form 13F-HR filings. See SEPN 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
The tracked-fund tape on SEPN is one-sided between 2026-Q1 and 2026-Q2: 70 added or opened and 13 trimmed or exited — on balance accumulating.
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
SEPN’s largest tracked holder by dollar value, RA CAPITAL MANAGEMENT, L.P., sizes it at 2.0% of its own reported 13F book, while the median holder sizes it at 0.0% of theirs — a 2.0pp conviction gap — its largest holder concentrates the name more heavily than the typical one.
Book-share is each fund’s reported value in SEPN 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 150 tracked filers holding SEPN, 95 increased or opened the position and 50 reduced or closed it; over the same quarter, open-market insider Form 4s were net sales.
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 SEPN 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 19
- Jupiter Topco LLC$44M
- LOOMIS SAYLES & CO L P$21M
- Woodline Partners LP$6M
- LAZARD ASSET MANAGEMENT LLC$3M
- DIMENSIONAL FUND ADVISORS LP$3M
- ARROWSTREET CAPITAL, LIMITED PARTNERSHIP$2M
Full exits 8
- BVF INC/IL$33M
- JANUS HENDERSON GROUP PLC$21M
- Venrock Adviser, LLC$12M
- Checkpoint Capital L.P.$2M
- MARSHALL WACE, LLP$957K
- ACADIAN ASSET MANAGEMENT LLC$741K
Largest adds
- RA CAPITAL MANAGEMENT, L.P.$66M
- TRV GP V, LLC$59M
- Driehaus Capital Management LLC$43M
- TRV GP VI, LLC$40M
- GOLDMAN SACHS GROUP INC$33M
- SAMSARA BIOCAPITAL, LLC$30M
Largest trims
- MILLENNIUM MANAGEMENT LLC$1M
- Invesco Ltd.$1M
- Rangeley Capital, LLC$715K
- Jump Financial, LLC$597K
- HUSSMAN STRATEGIC ADVISORS, INC.$413K
Institutional holders
One row per tracked fund, largest reported value first. “% of value” is the fund’s share of this security’s tracked institutional value — not of shares outstanding. Rows marked stale are from an earlier filing than the security’s latest quarter — that fund is absent from the newest snapshot (position exited, or reported under a different name).
| Fund | Shares | Reported value | % of value | Quarter |
|---|---|---|---|---|
| RA CAPITAL MANAGEMENT, L.P. | 6,995,858 | $234M | 13.7% | 2026-Q2 |
| TRV GP V, LLC | 6,215,591 | $208M | 12.2% | 2026-Q2 |
| Driehaus Capital Management LLC added | 4,433,058 | $148M | 8.7% | 2026-Q2 |
| TRV GP VI, LLC | 4,211,659 | $141M | 8.3% | 2026-Q2 |
| SAMSARA BIOCAPITAL, LLC | 3,149,128 | $105M | 6.2% | 2026-Q2 |
| GOLDMAN SACHS GROUP INC added | 3,062,766 | $103M | 6.0% | 2026-Q2 |
| BlackRock, Inc. added | 1,932,088 | $65M | 3.8% | 2026-Q2 |
| Siren, L.L.C. trimmed | 1,900,000 | $64M | 3.7% | 2026-Q2 |
| Avoro Capital Advisors LLC | 1,337,500 | $45M | 2.6% | 2026-Q2 |
| Jupiter Topco LLC new | 1,307,500 | $44M | 2.6% | 2026-Q2 |
| VANGUARD CAPITAL MANAGEMENT LLC added | 1,221,673 | $41M | 2.4% | 2026-Q2 |
| PRIMECAP MANAGEMENT CO/CA/ added | 1,167,382 | $39M | 2.3% | 2026-Q2 |
| First Light Asset Management, LLC added | 963,260 | $32M | 1.9% | 2026-Q2 |
| ADAR1 Capital Management, LLC trimmed | 940,747 | $32M | 1.8% | 2026-Q2 |
| GEODE CAPITAL MANAGEMENT, LLC added | 679,163 | $23M | 1.3% | 2026-Q2 |
| STATE STREET CORP added | 652,630 | $22M | 1.3% | 2026-Q2 |
| LOOMIS SAYLES & CO L P new | 624,752 | $21M | 1.2% | 2026-Q2 |
| Casdin Capital, LLC | 553,268 | $19M | 1.1% | 2026-Q2 |
| Catalio Capital Management, LP added | 536,152 | $18M | 1.1% | 2026-Q2 |
| ALGERT GLOBAL LLC added | 397,487 | $13M | 0.8% | 2026-Q2 |
| BALYASNY ASSET MANAGEMENT L.P. added | 350,442 | $12M | 0.7% | 2026-Q2 |
| Longaeva Partners L.P. added | 298,171 | $10M | 0.6% | 2026-Q2 |
| Soleus Capital Management, L.P. | 275,000 | $9M | 0.5% | 2026-Q2 |
| VANGUARD PORTFOLIO MANAGEMENT LLC added | 230,184 | $8M | 0.5% | 2026-Q2 |
| Universal- Beteiligungs- und Servicegesellschaft mbH trimmed | 222,702 | $7M | 0.4% | 2026-Q2 |
| TWO SIGMA INVESTMENTS, LP added | 220,885 | $7M | 0.4% | 2026-Q2 |
| NORTHERN TRUST CORP added | 201,131 | $7M | 0.4% | 2026-Q2 |
| Kalehua Capital Management LLC | 194,544 | $7M | 0.4% | 2026-Q2 |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC added | 187,041 | $6M | 0.4% | 2026-Q2 |
| Woodline Partners LP trimmed | 185,535 | $6M | 0.4% | 2026-Q2 |
| VANGUARD FIDUCIARY TRUST CO added | 165,656 | $6M | 0.3% | 2026-Q2 |
| MORGAN STANLEY added | 134,377 | $5M | 0.3% | 2026-Q2 |
| UBS Group AG trimmed | 89,874 | $3M | 0.2% | 2026-Q2 |
| JPMORGAN CHASE & CO added | 85,301 | $3M | 0.2% | 2026-Q2 |
| FEDERATED HERMES, INC. trimmed | 86,753 | $3M | 0.2% | 2026-Q2 |
| LAZARD ASSET MANAGEMENT LLC new | 75,425 | $3M | 0.1% | 2026-Q2 |
| DIMENSIONAL FUND ADVISORS LP new | 75,309 | $3M | 0.1% | 2026-Q2 |
| ARROWSTREET CAPITAL, LIMITED PARTNERSHIP new | 74,649 | $2M | 0.1% | 2026-Q2 |
| JACOBS LEVY EQUITY MANAGEMENT, INC added | 68,180 | $2M | 0.1% | 2026-Q2 |
| HUSSMAN STRATEGIC ADVISORS, INC. trimmed | 63,000 | $2M | 0.1% | 2026-Q2 |
| AMERICAN CENTURY COMPANIES INC trimmed | 60,973 | $2M | 0.1% | 2026-Q2 |
| Bank of New York Mellon Corp trimmed | 56,176 | $2M | 0.1% | 2026-Q2 |
| XTX Topco Ltd added | 54,489 | $2M | 0.1% | 2026-Q2 |
| MILLENNIUM MANAGEMENT LLC trimmed | 50,562 | $2M | 0.1% | 2026-Q2 |
| BARCLAYS PLC added | 49,821 | $2M | 0.1% | 2026-Q2 |
| Elmind Capital, LP new | 49,444 | $2M | 0.1% | 2026-Q2 |
| Nuveen, LLC added | 48,229 | $2M | 0.1% | 2026-Q2 |
| Sofinnova Investments, Inc. | 47,506 | $2M | 0.1% | 2026-Q2 |
| D. E. Shaw & Co., Inc. new | 46,483 | $2M | 0.1% | 2026-Q2 |
| JANE STREET GROUP, LLC added | 45,552 | $2M | 0.1% | 2026-Q2 |
| Voleon Capital Management LP new | 44,435 | $1M | 0.1% | 2026-Q2 |
| RENAISSANCE TECHNOLOGIES LLC added | 41,419 | $1M | 0.1% | 2026-Q2 |
| Russell Investments Group, Ltd. added | 40,209 | $1M | 0.1% | 2026-Q2 |
| Caption Management, LLC new | 38,006 | $1M | 0.1% | 2026-Q2 |
| BANK OF AMERICA CORP /DE/ added | 35,875 | $1M | 0.1% | 2026-Q2 |
| PRICE T ROWE ASSOCIATES INC /MD/ added | 35,323 | $1M | 0.1% | 2026-Q2 |
| Alyeska Investment Group, L.P. | 35,000 | $1M | 0.1% | 2026-Q2 |
| Brevan Howard Capital Management LP new | 29,452 | $986K | 0.1% | 2026-Q2 |
| HighVista Strategies LLC trimmed | 29,337 | $982K | 0.1% | 2026-Q2 |
| TUDOR INVESTMENT CORP ET AL added | 28,966 | $970K | 0.1% | 2026-Q2 |
| RHUMBLINE ADVISERS added | 27,636 | $926K | 0.1% | 2026-Q2 |
| Trexquant Investment LP trimmed | 25,645 | $859K | 0.1% | 2026-Q2 |
| Invesco Ltd. trimmed | 24,094 | $807K | 0.0% | 2026-Q2 |
| Logos Global Management LP | 23,548 | $789K | 0.0% | 2026-Q2 |
| FMR LLC trimmed | 23,240 | $778K | 0.0% | 2026-Q2 |
| FOX RUN MANAGEMENT, L.L.C. new | 22,038 | $738K | 0.0% | 2026-Q2 |
| DEUTSCHE BANK AG\ added | 21,873 | $733K | 0.0% | 2026-Q2 |
| ALLIANCEBERNSTEIN L.P. added | 29,900 | $718K | 0.0% | 2026-Q2 |
| Squarepoint Ops LLC added | 21,219 | $711K | 0.0% | 2026-Q2 |
| STRS OHIO added | 21,000 | $703K | 0.0% | 2026-Q2 |
| FRED ALGER MANAGEMENT, LLC new | 20,958 | $702K | 0.0% | 2026-Q2 |
| Jump Financial, LLC trimmed | 20,200 | $676K | 0.0% | 2026-Q2 |
| Swiss National Bank trimmed | 19,800 | $663K | 0.0% | 2026-Q2 |
| WELLS FARGO & COMPANY/MN added | 19,684 | $659K | 0.0% | 2026-Q2 |
| FRANKLIN RESOURCES INC added | 18,607 | $623K | 0.0% | 2026-Q2 |
| CITIGROUP INC added | 17,808 | $596K | 0.0% | 2026-Q2 |
| Aquatic Capital Management LLC new | 17,427 | $584K | 0.0% | 2026-Q2 |
| Engineers Gate Manager LP added | 17,350 | $581K | 0.0% | 2026-Q2 |
| BNP PARIBAS FINANCIAL MARKETS added | 16,946 | $568K | 0.0% | 2026-Q2 |
| LOS ANGELES CAPITAL MANAGEMENT LLC added | 16,597 | $556K | 0.0% | 2026-Q2 |
| State of Wyoming new | 16,379 | $549K | 0.0% | 2026-Q2 |
| Vanguard Global Advisers, LLC | 16,247 | $544K | 0.0% | 2026-Q2 |
| AQR CAPITAL MANAGEMENT LLC added | 15,397 | $516K | 0.0% | 2026-Q2 |
| VIRGINIA RETIREMENT SYSTEMS ET Al new | 13,300 | $445K | 0.0% | 2026-Q2 |
| VANGUARD GROUP INC trimmed | 1,508,195 | $42M | 2.5% | 2025-Q4 stale (2 quarters behind) |
| BVF INC/IL trimmed | 1,353,249 | $33M | 1.9% | 2026-Q1 stale (1 quarter behind) |
| JANUS HENDERSON GROUP PLC trimmed | 890,754 | $21M | 1.3% | 2026-Q1 stale (1 quarter behind) |
| Venrock Adviser, LLC trimmed | 506,056 | $12M | 0.7% | 2026-Q1 stale (1 quarter behind) |
| PERCEPTIVE ADVISORS LLC trimmed | 433,160 | $12M | 0.7% | 2025-Q4 stale (2 quarters behind) |
| Sio Capital Management, LLC trimmed | 189,199 | $4M | 0.2% | 2025-Q3 stale (3 quarters behind) |
| Checkpoint Capital L.P. trimmed | 100,300 | $2M | 0.1% | 2026-Q1 stale (1 quarter behind) |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP added | 166,506 | $2M | 0.1% | 2025-Q2 stale (4 quarters behind) |
| Walleye Capital LLC added | 80,341 | $2M | 0.1% | 2025-Q3 stale (3 quarters behind) |
| Deep Track Capital, LP trimmed | 121,716 | $1M | 0.1% | 2025-Q2 stale (4 quarters behind) |
| ExodusPoint Capital Management, LP new | 37,867 | $1M | 0.1% | 2025-Q4 stale (2 quarters behind) |
| MARSHALL WACE, LLP trimmed | 39,840 | $957K | 0.1% | 2026-Q1 stale (1 quarter behind) |
| ACADIAN ASSET MANAGEMENT LLC added | 30,978 | $741K | 0.0% | 2026-Q1 stale (1 quarter behind) |
| TWO SIGMA ADVISERS, LP added | 25,700 | $717K | 0.0% | 2025-Q4 stale (2 quarters behind) |
| Y-Intercept (Hong Kong) Ltd new | 25,770 | $619K | 0.0% | 2026-Q1 stale (1 quarter behind) |
| ADAGE CAPITAL PARTNERS GP, L.L.C. trimmed | 24,000 | $577K | 0.0% | 2026-Q1 stale (1 quarter behind) |
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.