GOSSNasdaqPharmaceutical PreparationsFiscal year ends December 31
Gossamer Bio, Inc.
Financials through Q2 FY2026, quarter ended Jun 30, 2026Last filing: 10-Q on Aug 13, 2026
$8.43−0.34 (-3.88%)
Close on Oct 19, 2026
- Market cap
- $2.77B
- P/E (TTM)
- –
- Dividend yield
- –
Ownership
Institutional holdings as of Jun 30, 2026, from 13F filings
Held by institutions
78.1%
382M of 489M shares
Institutional holders
170
28 new, 42 sold out
Net institutional buying
205M
In Q2 2026
Insider trades, 12 months
0 buys · 0 sales
Open-market trades only
Shares held by institutions
Holders of more than 5%
Latest Schedule 13D (active) or 13G (passive) filed by each holder
| Holder | Shares | % of class | Filing | As of |
|---|---|---|---|---|
| Ari Zweiman | 49,868,571 | 9.99% | 13G (passive) | Jun 4, 2026 |
| Michael S. Rosen | 48,835,788 | 9.90% | 13G (passive) | Jun 4, 2026 |
| Kai Zheng | 37,665,073 | 7.70% | 13G (passive) | Jun 4, 2026 |
| David E. Shaw | 369,459 | 6.00% | 13D (active) amendment | Oct 6, 2026 |
| D. E. Shaw & Co., L.P. | 34,609,565 | 7.10% | 13D (active) amendment | Jul 22, 2026 |
| D. E. Shaw & Co., L.L.C. | 29,128,194 | 6.00% | 13D (active) amendment | Aug 20, 2026 |
| James Silverman | 24,942,565 | 5.10% | 13G (passive) | Jul 22, 2026 |
| Octagon Investments Master Fund | 19,576,054 | 8.60% | 13G (passive) | Dec 31, 2024 |
| Artal Group S.A. | 13,108,880 | 5.80% | 13G (passive) | Dec 14, 2023 |
Top institutional holders
13F holdings as of Jun 30, 2026
| Holder | Shares | % of GOSS | Value | Change | % of portfolio |
|---|---|---|---|---|---|
| D. E. Shaw & Co., Inc. | 40,959,285 | 8.38% | $6.74M | +40,569,854 | 0.00% |
| 683 Capital Management, LLC | 39,198,868 | 8.02% | $6.45M | +34,198,868 | 0.32% |
| DeepCurrents Investment Group LLC | 37,665,073 | 7.70% | $6.03M | New | 0.18% |
| Context Capital Management, LLC | 28,946,459 | 5.92% | $4.76M | New | 0.09% |
| Worth Venture Partners, LLC | 25,017,881 | 5.12% | $4.12M | New | 9.29% |
| Kalehua Capital Management LLC | 22,298,726 | 4.56% | $3.67M | +4,590,593 | 1.17% |
| Aqr Capital Management LLC | 15,629,993 | 3.20% | $2.57M | +5,503,096 | 0.00% |
| Gsa Capital Partners Llp | 14,986,947 | 3.07% | $2.47K | +11,732,714 | 0.16% |
| Wolverine Asset Management LLC | 12,894,746 | 2.64% | $2.12M | New | 0.02% |
| Renaissance Technologies LLC | 11,629,896 | 2.38% | $1.91M | +10,412,028 | 0.00% |
| Vanguard Capital Management LLC | 9,416,023 | 1.93% | $1.55M | +21,430 | 0.00% |
| ARCH Venture Management, LLC | 8,055,916 | 1.65% | $1.33M | – | 0.12% |
| Barclays PLC | 7,832,522 | 1.60% | $1.29M | +4,766,716 | 0.00% |
| Octagon Capital Advisors LP | 7,750,000 | 1.59% | $1.28M | – | 0.11% |
| BlackRock, Inc. | 7,669,943 | 1.57% | $1.26M | −9,156,752 | 0.00% |
| Arrowstreet Capital, Limited Partnership | 7,573,388 | 1.55% | $1.25M | New | 0.00% |
| Two Sigma Investments, LP | 7,432,001 | 1.52% | $1.22M | +2,651,150 | 0.00% |
| Samsara BioCapital, LLC | 7,222,559 | 1.48% | $1.19M | – | 0.10% |
| Qube Research & Technologies Ltd | 7,065,756 | 1.45% | $1.16M | +2,147,993 | 0.00% |
| Corient Private Wealth LLC | 5,632,698 | 1.15% | $927.14K | +1,647,315 | 0.00% |
Institutional buying and selling by quarter
Positions opened, added to, reduced and closed by 13F filers
| Quarter | Holders | Shares held | % of shares | New / added | Reduced / closed | Shares bought | Shares sold |
|---|---|---|---|---|---|---|---|
| Q2 2026 | 170 | 382M | 78.1% | 28 / 63 | 44 / 42 | 244M | 40M |
| Q1 2026 | 185 | 177M | 36.3% | 47 / 71 | 49 / 54 | 73M | 71M |
| Q4 2025 | 195 | 189M | 38.6% | 49 / 69 | 49 / 14 | 34M | 25M |
| Q3 2025 | 164 | 180M | 36.9% | 56 / 49 | 44 / 14 | 32M | 29M |
| Q2 2025 | 123 | 177M | 36.2% | 33 / 41 | 24 / 28 | 27M | 20M |
| Q1 2025 | 118 | 170M | 34.7% | 23 / 34 | 32 / 9 | 12M | 14M |
| Q4 2024 | 105 | 172M | 35.2% | 18 / 32 | 27 / 13 | 24M | 27M |
| Q3 2024 | 100 | 175M | 35.9% | 17 / 25 | 31 / 10 | 22M | 27M |
| Q2 2024 | 94 | 184M | 37.6% | 11 / 32 | 29 / 26 | 27M | 50M |
| Q1 2024 | 109 | 207M | 42.3% | 26 / 27 | 31 / 15 | 17M | 26M |
| Q4 2023 | 98 | 216M | 44.1% | 22 / 33 | 23 / 19 | 54M | 44M |
| Q3 2023 | 95 | 206M | 42.1% | 31 / 31 | 19 / 34 | 153M | 9M |
Top mutual fund and ETF holders
Latest monthly portfolio reports (Form N-PORT)
| Fund | Shares | % of GOSS | Value | % of fund | As of |
|---|---|---|---|---|---|
| Vanguard Total Stock Market Index Fund | 6,910,934 | 1.41% | $1.14M | 0.00% | Jun 30, 2026 |
| Vanguard Extended Market Index Fund | 2,243,305 | 0.46% | $369.25K | 0.00% | Jun 30, 2026 |
| iShares Biotechnology ETF | 1,501,116 | 0.31% | $247.08K | 0.00% | Jun 30, 2026 |
| Fidelity Extended Market Index Fund | 1,150,857 | 0.24% | $265.73K | 0.00% | May 31, 2026 |
| Schwab U.S. Small-Cap ETF | 986,826 | 0.20% | $227.86K | 0.00% | May 31, 2026 |
| Vanguard Russell 2000 Index Fund | 977,030 | 0.20% | $225.60K | 0.00% | May 31, 2026 |
| Invesco RAFI US 1500 Small-Mid ETF | 556,395 | 0.11% | $94.31K | 0.00% | Jul 31, 2026 |
| Vanguard Health Care Index Fund | 541,950 | 0.11% | $125.14K | 0.00% | May 31, 2026 |
| Fidelity Total Market Index Fund | 381,135 | 0.08% | $88.00K | 0.00% | May 31, 2026 |
| BlackRock Health Sciences Opportunities Portfolio | 365,199 | 0.07% | $84.32K | 0.00% | May 29, 2026 |
| Fidelity Series Total Market Index Fund | 300,421 | 0.06% | $69.37K | 0.00% | May 31, 2026 |
| iShares Core S&P Total U.S. Stock Market ETF | 294,007 | 0.06% | $48.39K | 0.00% | Jun 30, 2026 |
| Goldman Sachs Absolute Return Tracker Fund | 267,245 | 0.05% | $43.99K | 0.00% | Jun 30, 2026 |
| Eventide Small Cap ETF | 204,551 | 0.04% | $34.67K | 0.10% | Jul 31, 2026 |
| Vanguard Russell 2000 Growth Index Fund | 180,256 | 0.04% | $41.62K | 0.00% | May 31, 2026 |
Officers, directors and major owners
People who filed Forms 3, 4 or 5 in the last two years
| Name | Role | Shares owned | % of shares | Latest filing |
|---|---|---|---|---|
| Faheem Hasnain | President & CEO, Director | 6,245,866 | 1.28% | Aug 26, 2026 |
| Caryn Peterson | Chief Development Officer | 259,333 | 0.05% | Aug 26, 2026 |
| Waage Christian | EVP, Tech Ops and Admin | 882,175 | 0.18% | Aug 26, 2026 |
| Bryan Giraudo | COO/CFO | 869,747 | 0.18% | Aug 26, 2026 |
| Robert Paul Smith JR | Chief Commercial Officer | 285,898 | 0.06% | Aug 26, 2026 |
| Richard Aranda | Chief Medical Officer | 465,645 | 0.10% | Mar 20, 2026 |
| Russell J. Cox | Director | 7,200 | 0.00% | Sep 25, 2026 |
| John D. Quisel | Director | – | – | Sep 25, 2026 |
| Gregory Austin Ciongoli | Director | – | – | Sep 25, 2026 |
| Skye Drynan | Director | – | – | Sep 25, 2026 |
| Sandra Milligan | Director | 90,050 | 0.02% | Sep 25, 2026 |
| Steven D. Nathan | Director | – | – | Sep 25, 2026 |
| Thomas O. Daniel | Director | 38,095 | 0.01% | Sep 25, 2026 |
Insider trades
Common stock transactions reported on Form 4, newest first
| Insider | Date | Transaction | Shares | Price | Value | Shares after |
|---|---|---|---|---|---|---|
| Robert Paul Smith JR Chief Commercial Officer | Jan 2, 2026 | Award | +93,750 | – | – | 260,898 |
| Caryn Peterson EVP, Regulatory Affairs | Jan 2, 2026 | Award | +84,500 | – | – | 259,333 |
| Richard Aranda Chief Medical Officer | Jan 2, 2026 | Award | +93,750 | – | – | 463,106 |
| Faheem Hasnain President & CEO, Director | Jan 2, 2026 | Award | +280,000 | – | – | 837,793 |
| Waage Christian EVP, Tech Ops and Admin | Jan 2, 2026 | Award | +84,500 | – | – | 814,061 |
| Bryan Giraudo COO/CFO | Jan 2, 2026 | Award | +115,750 | – | – | 389,737 |
| Faheem Hasnain President & CEO, Director | Oct 1, 2025 | Award | +437,500 | – | – | 557,793 |
| Richard Aranda Chief Medical Officer | Oct 1, 2025 | Award | +162,500 | – | – | 369,356 |
| Caryn Peterson EVP, Regulatory Affairs | Oct 1, 2025 | Award | +125,000 | – | – | 174,833 |
| Bryan Giraudo COO/CFO | Oct 1, 2025 | Award | +181,250 | – | – | 273,987 |
| Robert Paul Smith JR Chief Commercial Officer | Oct 1, 2025 | Award | +162,500 | – | – | 162,500 |
| Waage Christian EVP, Tech Ops and Admin | Oct 1, 2025 | Award | +125,000 | – | – | 710,934 |
| Sandra Milligan Director | Aug 19, 2025 | Buy | +26,050 | $1.92 | $50.02K | 58,050 |
| Richard Aranda Chief Medical Officer | Jun 24, 2024 | Sale | −1,908 | $0.66 | $1.26K | 196,891 |
| Faheem Hasnain President & CEO, Director | Jun 21, 2024 | Buy | +372,000 | $0.67 | $249.24K | 5,408,073 |
| Bryan Giraudo COO/CFO | Jun 18, 2024 | Buy | +100,000 | $0.59 | $59.00K | 480,010 |
| Robert Paul Smith JR Chief Commercial Officer | Jun 17, 2024 | Buy | +25,000 | $0.60 | $15.00K | 25,000 |
| Waage Christian EVP, Tech Ops and Admin | Mar 27, 2024 | Sale | −6,430 | $1.16 | $7.46K | 585,934 |
| Bryan Giraudo COO/CFO | Mar 27, 2024 | Sale | −6,430 | $1.16 | $7.46K | 92,737 |
| Faheem Hasnain President & CEO, Director | Mar 27, 2024 | Sale | −23,172 | $1.16 | $26.88K | 120,293 |
| Richard Aranda Chief Medical Officer | Mar 18, 2024 | Sale | −4,018 | $1.33 | $5.34K | 198,799 |
| Caryn Peterson EVP, Regulatory Affairs | Mar 18, 2024 | Sale | −4,018 | $1.33 | $5.34K | 49,833 |
| Sandra Milligan Director | Nov 15, 2023 | Buy | +32,000 | $0.79 | $25.28K | 32,000 |
| Bryan Giraudo COO/CFO | Nov 13, 2023 | Buy | +200,000 | $0.56 | $112.00K | 380,010 |
| Faheem Hasnain President & CEO, Director | Jul 24, 2023 | Award | +540,176 | $1.82 | $983.12K | 5,036,073 |
| Waage Christian EVP, Tech Ops and Admin | Jul 24, 2023 | Award | +13,504 | $1.82 | $24.58K | 45,892 |
| Bryan Giraudo COO/CFO | Jul 24, 2023 | Award | +54,020 | $1.82 | $98.32K | 180,010 |
| Richard Aranda Chief Medical Officer | Jun 22, 2023 | Sale | −1,814 | $1.29 | $2.34K | 197,574 |
| Bryan Giraudo COO/CFO | Apr 4, 2023 | Buy | +55,000 | $1.02 | $56.10K | 125,990 |
| Faheem Hasnain President & CEO, Director | Mar 22, 2023 | Buy | +440,500 | $1.14 | $502.17K | 4,495,897 |
| Faheem Hasnain President & CEO, Director | Mar 21, 2023 | Buy | +269,389 | $1.20 | $323.27K | 4,055,397 |
| Waage Christian EVP, Tech Ops and Admin | Mar 20, 2023 | Buy | +18,500 | $1.20 | $22.20K | 32,388 |
| Faheem Hasnain President & CEO, Director | Mar 20, 2023 | Buy | +168,683 | $1.03 | $173.74K | 3,786,008 |
| Bryan Giraudo COO/CFO | Mar 20, 2023 | Buy | +50,000 | $0.97 | $48.50K | 70,990 |
| Caryn Peterson EVP, Regulatory Affairs | Mar 16, 2023 | Sale | −7,564 | $1.10 | $8.32K | 53,851 |
| Laura Carter Chief Scientific Officer | Mar 16, 2023 | Sale | −6,029 | $1.10 | $6.63K | 76,263 |
| Richard Aranda Chief Medical Officer | Mar 16, 2023 | Sale | −7,563 | $1.10 | $8.32K | 199,388 |
| Laura Carter Chief Scientific Officer | Oct 24, 2022 | Sale | −4,876 | $12.07 | $58.85K | 82,292 |
| Caryn Peterson EVP, Regulatory Affairs | Oct 24, 2022 | Sale | −4,757 | $12.07 | $57.42K | 61,415 |
| Richard Aranda Chief Medical Officer | Oct 24, 2022 | Sale | −4,757 | $12.07 | $57.42K | 205,430 |
| Laura Carter Chief Scientific Officer | Oct 24, 2022 | Sale | −4,876 | $12.07 | $58.85K | 82,292 |
| Laura Carter Chief Scientific Officer | Jul 15, 2022 | Buy | +6,934 | $7.21 | $49.99K | 87,168 |
| Waage Christian EVP, Tech Ops and Admin | Jul 15, 2022 | Buy | +6,934 | $7.21 | $49.99K | 13,888 |
| Bryan Giraudo COO/CFO | Jul 15, 2022 | Buy | +13,869 | $7.21 | $100.00K | 20,990 |
| Faheem Hasnain President & CEO, Director | Jul 15, 2022 | Buy | +138,696 | $7.21 | $1,000.00K | 3,617,325 |
| Laura Carter Chief Scientific Officer | Jul 1, 2022 | Sale | −8,808 | $8.25 | $72.67K | 80,234 |
| Richard Aranda Chief Medical Officer | Jun 22, 2022 | Sale | −1,778 | $6.88 | $12.23K | 209,897 |
| Laura Carter Chief Scientific Officer | May 4, 2022 | Sale | −1,262 | $7.20 | $9.09K | 89,042 |
| Waage Christian EVP, Tech Ops and Admin | Mar 23, 2022 | Sale | −10,722 | $8.92 | $95.64K | 579,008 |
| Faheem Hasnain President & CEO, Director | Mar 23, 2022 | Sale | −19,035 | $8.92 | $169.79K | 143,465 |
| Bryan Giraudo COO/CFO | Mar 23, 2022 | Sale | −10,722 | $8.92 | $95.64K | 99,167 |
| Laura Carter Chief Scientific Officer | Mar 16, 2022 | Sale | −5,002 | $8.28 | $41.42K | 90,304 |
| Richard Aranda Chief Medical Officer | Mar 16, 2022 | Sale | −6,278 | $8.28 | $51.98K | 211,675 |
| Caryn Peterson EVP, Regulatory Affairs | Mar 16, 2022 | Sale | −6,279 | $8.28 | $51.99K | 66,172 |
| Laura Carter Chief Scientific Officer | Oct 25, 2021 | Sale | −2,377 | $12.25 | $29.12K | 95,306 |
| Richard Aranda Chief Medical Officer | Oct 25, 2021 | Sale | −2,377 | $12.25 | $29.12K | 217,432 |
| Caryn Peterson EVP, Regulatory Affairs | Oct 25, 2021 | Sale | −2,377 | $12.25 | $29.12K | 72,451 |
| Laura Carter Chief Scientific Officer | Jun 30, 2021 | Award | +25,000 | – | – | 97,683 |
| Richard Aranda Chief Medical Officer | Jun 21, 2021 | Award | +15,000 | – | – | 219,809 |
| Laura Carter Chief Scientific Officer | May 3, 2021 | Award | +10,820 | – | – | 72,683 |
Awards, option exercises, tax withholding and gifts are shown alongside open-market buys and sales. Each name links to the filing on SEC EDGAR.