Who owns Gossamer Bio (GOSS)
Which tracked institutional funds hold GOSS, how they are positioned, and who is buying versus exiting — from SEC Form 13F-HR filings. See GOSS 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
10 tracked funds added or opened GOSS while 29 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
GOSS’s largest tracked holder by dollar value, D. E. Shaw & Co., Inc., sizes it at 0.0% of its own reported 13F book, while the median holder sizes it at 0.0% of theirs — a 0.0pp conviction gap — its largest holder concentrates the name more heavily than the typical one.
Book-share is each fund’s reported value in GOSS 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 164 tracked filers holding GOSS, 86 increased or opened the position and 92 reduced or closed it; over the same quarter, there were no open-market insider Form 4s.
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 GOSS 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 5
- DeepCurrents Investment Group LLC$6M
- Context Capital Management, LLC$5M
- Worth Venture Partners, LLC$4M
- WOLVERINE ASSET MANAGEMENT LLC$2M
- ARROWSTREET CAPITAL, LIMITED PARTNERSHIP$1M
Full exits 6
- ACADIAN ASSET MANAGEMENT LLC$2M
- GSA CAPITAL PARTNERS LLP$1M
- Monashee Investment Management LLC$845K
- ALLIANCEBERNSTEIN L.P.$590K
- Rock Springs Capital Management LP$529K
- MACKENZIE FINANCIAL CORP$505K
Largest adds
- D. E. Shaw & Co., Inc.$7M
- 683 Capital Management, LLC$5M
- RENAISSANCE TECHNOLOGIES LLC$2M
- MILLENNIUM MANAGEMENT LLC$334K
- BARCLAYS PLC$282K
Largest trims
- BlackRock, Inc.$4M
- BALYASNY ASSET MANAGEMENT L.P.$2M
- VANGUARD CAPITAL MANAGEMENT LLC$2M
- ARCH Venture Management, LLC$1M
- Octagon Capital Advisors LP$1M
- STATE STREET CORP$1M
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 |
|---|---|---|---|---|
| D. E. Shaw & Co., Inc. added | 40,959,285 | $7M | 11.7% | 2026-Q2 |
| 683 Capital Management, LLC added | 39,198,868 | $6M | 11.2% | 2026-Q2 |
| DeepCurrents Investment Group LLC new | 37,665,073 | $6M | 10.4% | 2026-Q2 |
| Context Capital Management, LLC new | 28,946,459 | $5M | 8.2% | 2026-Q2 |
| Worth Venture Partners, LLC new | 25,017,881 | $4M | 7.1% | 2026-Q2 |
| AQR CAPITAL MANAGEMENT LLC added | 15,629,993 | $3M | 4.5% | 2026-Q2 |
| WOLVERINE ASSET MANAGEMENT LLC new | 12,894,746 | $2M | 3.7% | 2026-Q2 |
| RENAISSANCE TECHNOLOGIES LLC added | 11,629,896 | $2M | 3.3% | 2026-Q2 |
| Kalehua Capital Management LLC added | 11,149,363 | $2M | 3.2% | 2026-Q2 |
| VANGUARD CAPITAL MANAGEMENT LLC added | 9,416,023 | $2M | 2.7% | 2026-Q2 |
| ARCH Venture Management, LLC | 8,055,916 | $1M | 2.3% | 2026-Q2 |
| BARCLAYS PLC added | 7,832,522 | $1M | 2.2% | 2026-Q2 |
| Octagon Capital Advisors LP | 7,750,000 | $1M | 2.2% | 2026-Q2 |
| BlackRock, Inc. trimmed | 7,669,943 | $1M | 2.2% | 2026-Q2 |
| ARROWSTREET CAPITAL, LIMITED PARTNERSHIP added | 7,573,388 | $1M | 2.2% | 2026-Q2 |
| TWO SIGMA INVESTMENTS, LP added | 7,432,001 | $1M | 2.1% | 2026-Q2 |
| SAMSARA BIOCAPITAL, LLC | 7,222,559 | $1M | 2.1% | 2026-Q2 |
| Qube Research & Technologies Ltd added | 7,065,756 | $1M | 2.0% | 2026-Q2 |
| Corient Private Wealth LP added | 5,625,509 | $926K | 1.6% | 2026-Q2 |
| Siren, L.L.C. | 5,208,968 | $857K | 1.5% | 2026-Q2 |
| HHLR ADVISORS, LTD. | 4,974,041 | $819K | 1.4% | 2026-Q2 |
| UBS Group AG added | 3,093,785 | $510K | 0.9% | 2026-Q2 |
| Squarepoint Ops LLC trimmed | 2,556,378 | $421K | 0.7% | 2026-Q2 |
| GEODE CAPITAL MANAGEMENT, LLC trimmed | 2,481,605 | $409K | 0.7% | 2026-Q2 |
| MILLENNIUM MANAGEMENT LLC added | 2,402,633 | $395K | 0.7% | 2026-Q2 |
| MB Generational Wealth, LLC added | 2,217,451 | $365K | 0.6% | 2026-Q2 |
| JACOBS LEVY EQUITY MANAGEMENT, INC added | 2,187,402 | $360K | 0.6% | 2026-Q2 |
| MARSHALL WACE, LLP added | 2,114,988 | $338K | 0.6% | 2026-Q2 |
| Alyeska Investment Group, L.P. | 2,051,442 | $338K | 0.6% | 2026-Q2 |
| HSBC HOLDINGS PLC added | 1,583,118 | $267K | 0.5% | 2026-Q2 |
| Ensign Peak Advisors, Inc trimmed | 1,450,979 | $239K | 0.4% | 2026-Q2 |
| VANGUARD FIDUCIARY TRUST CO trimmed | 1,245,392 | $205K | 0.4% | 2026-Q2 |
| JPMORGAN CHASE & CO added | 1,228,634 | $201K | 0.3% | 2026-Q2 |
| GOLDMAN SACHS GROUP INC trimmed | 1,128,451 | $186K | 0.3% | 2026-Q2 |
| STATE STREET CORP trimmed | 1,114,718 | $183K | 0.3% | 2026-Q2 |
| DEUTSCHE BANK AG\ trimmed | 1,106,441 | $188K | 0.3% | 2026-Q2 |
| Hennion & Walsh Asset Management, Inc. added | 1,098,914 | $181K | 0.3% | 2026-Q2 |
| NEA Management Company, LLC | 1,000,000 | $165K | 0.3% | 2026-Q2 |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC trimmed | 992,527 | $163K | 0.3% | 2026-Q2 |
| SMITH, MOORE & CO. added | 900,000 | $148K | 0.3% | 2026-Q2 |
| Ishara Investments LP | 820,000 | $135K | 0.2% | 2026-Q2 |
| PANAGORA ASSET MANAGEMENT INC added | 733,216 | $121K | 0.2% | 2026-Q2 |
| Mariner, LLC added | 594,719 | $98K | 0.2% | 2026-Q2 |
| IEQ CAPITAL, LLC added | 591,254 | $97K | 0.2% | 2026-Q2 |
| VANGUARD PORTFOLIO MANAGEMENT LLC trimmed | 544,212 | $90K | 0.2% | 2026-Q2 |
| CHOREO, LLC added | 540,111 | $89K | 0.2% | 2026-Q2 |
| TUDOR INVESTMENT CORP ET AL added | 479,581 | $79K | 0.1% | 2026-Q2 |
| NORTHERN TRUST CORP trimmed | 458,498 | $75K | 0.1% | 2026-Q2 |
| Invesco Ltd. trimmed | 442,268 | $73K | 0.1% | 2026-Q2 |
| BANK OF AMERICA CORP /DE/ trimmed | 396,727 | $65K | 0.1% | 2026-Q2 |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP added | 383,049 | $63K | 0.1% | 2026-Q2 |
| LPL Financial LLC trimmed | 332,534 | $55K | 0.1% | 2026-Q2 |
| MERCER GLOBAL ADVISORS INC /ADV added | 297,863 | $49K | 0.1% | 2026-Q2 |
| WADDELL & ASSOCIATES, LLC added | 261,798 | $43K | 0.1% | 2026-Q2 |
| MORGAN STANLEY trimmed | 241,591 | $40K | 0.1% | 2026-Q2 |
| PRUDENTIAL FINANCIAL INC added | 227,550 | $37K | 0.1% | 2026-Q2 |
| ADAR1 Capital Management, LLC trimmed | 212,531 | $35K | 0.1% | 2026-Q2 |
| Creative Planning added | 211,955 | $35K | 0.1% | 2026-Q2 |
| Merit Financial Group, LLC added | 169,596 | $28K | 0.0% | 2026-Q2 |
| EVENTIDE ASSET MANAGEMENT, LLC new | 163,440 | $27K | 0.0% | 2026-Q2 |
| Cerity Partners LLC added | 160,399 | $26K | 0.0% | 2026-Q2 |
| WEALTH ENHANCEMENT ADVISORY SERVICES, LLC added | 153,902 | $22K | 0.0% | 2026-Q2 |
| Sivia Capital Partners, LLC added | 152,298 | $25K | 0.0% | 2026-Q2 |
| Tower Research Capital LLC (TRC) added | 144,473 | $24K | 0.0% | 2026-Q2 |
| Schonfeld Strategic Advisors LLC trimmed | 132,888 | $22K | 0.0% | 2026-Q2 |
| FMR LLC added | 130,325 | $21K | 0.0% | 2026-Q2 |
| Russell Investments Group, Ltd. trimmed | 121,039 | $20K | 0.0% | 2026-Q2 |
| OSAIC HOLDINGS, INC. added | 120,204 | $19K | 0.0% | 2026-Q2 |
| GROUP ONE TRADING LLC added | 110,927 | $18K | 0.0% | 2026-Q2 |
| Arax Advisory Partners added | 108,204 | $18K | 0.0% | 2026-Q2 |
| BCV Asset Management Inc. | 106,500 | $18K | 0.0% | 2026-Q2 |
| Rockefeller Capital Management L.P. trimmed | 105,866 | $17K | 0.0% | 2026-Q2 |
| BALYASNY ASSET MANAGEMENT L.P. trimmed | 104,232 | $17K | 0.0% | 2026-Q2 |
| COMMONWEALTH EQUITY SERVICES, LLC trimmed | 101,993 | $17K | 0.0% | 2026-Q2 |
| Quarry LP | 100,000 | $16K | 0.0% | 2026-Q2 |
| Focus Partners Wealth added | 92,848 | $15K | 0.0% | 2026-Q2 |
| RHUMBLINE ADVISERS trimmed | 88,599 | $15K | 0.0% | 2026-Q2 |
| CAPTRUST FINANCIAL ADVISORS added | 81,778 | $13K | 0.0% | 2026-Q2 |
| Vanguard Global Advisers, LLC | 79,682 | $13K | 0.0% | 2026-Q2 |
| BNP PARIBAS FINANCIAL MARKETS trimmed | 73,693 | $12K | 0.0% | 2026-Q2 |
| Caprock Group, LLC | 70,000 | $12K | 0.0% | 2026-Q2 |
| Velan Capital Investment Management LP | 70,000 | $12K | 0.0% | 2026-Q2 |
| AlphaCore Capital LLC added | 69,482 | $11K | 0.0% | 2026-Q2 |
| Bronte Capital Management Pty Ltd. new | 67,754 | $11K | 0.0% | 2026-Q2 |
| TWO SIGMA SECURITIES, LLC added | 58,064 | $10K | 0.0% | 2026-Q2 |
| Integrated Wealth Concepts LLC added | 55,533 | $9K | 0.0% | 2026-Q2 |
| Bull Harbor Capital LLC added | 51,235 | $8K | 0.0% | 2026-Q2 |
| Beacon Pointe Advisors, LLC added | 48,000 | $8K | 0.0% | 2026-Q2 |
| Bank of New York Mellon Corp trimmed | 45,713 | $8K | 0.0% | 2026-Q2 |
| Y-Intercept (Hong Kong) Ltd new | 43,210 | $7K | 0.0% | 2026-Q2 |
| Prospera Financial Services Inc new | 42,123 | $7K | 0.0% | 2026-Q2 |
| Skaana Management L.P. | 40,200 | $7K | 0.0% | 2026-Q2 |
| Curi Capital, LLC added | 39,784 | $7K | 0.0% | 2026-Q2 |
| Vanguard Personalized Indexing Management, LLC added | 39,060 | $6K | 0.0% | 2026-Q2 |
| China Universal Asset Management Co., Ltd. trimmed | 37,352 | $6K | 0.0% | 2026-Q2 |
| Vickerman Investment Advisors, Inc. | 34,787 | $6K | 0.0% | 2026-Q2 |
| BRIGHTON JONES LLC added | 32,308 | $5K | 0.0% | 2026-Q2 |
| Cetera Investment Advisers | 30,749 | $5K | 0.0% | 2026-Q2 |
| Essential Partners LLC added | 30,225 | $5K | 0.0% | 2026-Q2 |
| StoneX Group Inc. new | 27,556 | $6K | 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.