SELLAS LIFE SCIENCES GROUP I SLS
COM NEW · Common Stock · CUSIP 81642T209
Company in San Ramon, United States
- SectorHealth care
- IndustryPharmaceutical Preparations
- HeadquartersNew York, NY
- Founded2006
- Websitegalenabiopharma.com
- FilingsSEC EDGAR
* Summed across managers. Shares that two managers' reports both contain – a subsidiary's holdings that its parent's report includes too, or a sub-adviser's in its client's – are counted once ($827 this quarter). Holder counts are more reliable. Shares outstanding: 201.9m as of 2026-08-10, from the company's own SEC filing; the percentage can still exceed 100%: lent-out shares are counted by the lender and the buyer, and some reports overlap without saying so. Implied quarter-end price ≈ $14.65. Options: 19 managers hold calls ($334.9m notional), 30 hold puts ($274.7m).
Trends to Q2 2026
Institutional holders
Managers reporting a position, each quarter
Numbers
| Quarter | Holders |
|---|---|
| Q3 2022 | 29 |
| Q4 2022 | 30 |
| Q1 2023 | 23 |
| Q2 2023 | 26 |
| Q3 2023 | 29 |
| Q4 2023 | 32 |
| Q1 2024 | 31 |
| Q2 2024 | 31 |
| Q3 2024 | 34 |
| Q4 2024 | 32 |
| Q1 2025 | 46 |
| Q2 2025 | 80 |
| Q3 2025 | 94 |
| Q4 2025 | 112 |
| Q1 2026 | 160 |
| Q2 2026 | 192 |
Buyers vs sellers
Managers adding to or starting a position, vs cutting or selling out
Numbers
| Quarter | Bought or added | Cut or sold out |
|---|---|---|
| Q3 2024 | 18 | 9 |
| Q4 2024 | 14 | 13 |
| Q1 2025 | 36 | 6 |
| Q2 2025 | 61 | 13 |
| Q3 2025 | 51 | 23 |
| Q4 2025 | 76 | 28 |
| Q1 2026 | 113 | 34 |
| Q2 2026 | 137 | 51 |
Calls vs puts
Options held, notional value, last 4 quarters. P/C = puts ÷ calls
Numbers
| Quarter | Calls | Puts | P/C |
|---|---|---|---|
| Q3 2025 | $27.8m | $332.9k | 0.01 |
| Q4 2025 | $81.5m | $9.0m | 0.11 |
| Q1 2026 | $102.0m | $11.3m | 0.11 |
| Q2 2026 | $334.9m | $274.7m | 0.82 |
Biggest buyers
| STATE STREET CORP | Added | +4.6m |
| Anson Funds Management LP | New | +4.5m |
| BlackRock, Inc. | Added | +2.9m |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Added | +1.7m |
| BNP PARIBAS FINANCIAL MARKETS | Added | +1.0m |
| GEODE CAPITAL MANAGEMENT, LLC | Added | +971.6k |
| VANGUARD CAPITAL MANAGEMENT LLC | Added | +700.2k |
| VANGUARD PORTFOLIO MANAGEMENT LLC | Added | +698.3k |
| JONES FINANCIAL COMPANIES LLLP | Added | +629.5k |
| JANE STREET GROUP, LLC | New | +508.4k |
Biggest sellers
| MARSHALL WACE, LLP | Sold out | -2.0m |
| TWO SIGMA INVESTMENTS, LP | Sold out | -403.2k |
| Invesco Ltd. | Reduced | -322.7k |
| VISION FINANCIAL MARKETS LLC | Reduced | -294.6k |
| Nuveen, LLC | Reduced | -252.2k |
| Virtu Financial LLC | Sold out | -221.8k |
| MILLENNIUM MANAGEMENT LLC | Sold out | -159.5k |
| SIMPLEX TRADING, LLC | Reduced | -141.1k |
| MORGAN STANLEY | Reduced | -100.0k |
| Balyasny Asset Management L.P. | Sold out | -81.7k |
Biggest calls
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Reduced | $105.6m7.2m shares |
| GROUP ONE TRADING LLC | Reduced | $98.1m6.6m shares |
| CITADEL ADVISORS LLC | Reduced | $64.2m4.3m shares |
| SIMPLEX TRADING, LLC | Reduced | $17.3m1.2m shares |
| Anson Funds Management LP | New | $11.8m800.0k shares |
| JANE STREET GROUP, LLC | Added | $11.1m749.2k shares |
| NOMURA HOLDINGS INC | Reduced | $6.3m425.0k shares |
| DIADEMA PARTNERS LP | Added | $5.9m400.0k shares |
| HRT FINANCIAL LP | Reduced | $5.3m357.6k shares |
| MILLENNIUM MANAGEMENT LLC | Reduced | $2.9m196.2k shares |
Biggest puts
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Added | $61.8m4.2m shares |
| CITADEL ADVISORS LLC | Added | $33.3m2.3m shares |
| Anson Funds Management LP | New | $27.2m1.8m shares |
| PERCEPTIVE ADVISORS LLC | New | $22.1m1.5m shares |
| GROUP ONE TRADING LLC | Added | $18.9m1.3m shares |
| Sio Capital Management, LLC | New | $18.2m1.2m shares |
| BNP PARIBAS FINANCIAL MARKETS | New | $15.4m10.4k shares |
| MILLENNIUM MANAGEMENT LLC | Added | $13.4m906.0k shares |
| BARCLAYS PLC | New | $11.8m801.6k shares |
| Balyasny Asset Management L.P. | New | $7.4m500.0k shares |
Options at notional value: the value of the shares the contracts control, as filers report them, not what the options cost. Not included in the holders, shares or buying above.
Major shareholders (over 5%)
Anyone who owns more than 5% of a class of the company's shares has to say so: on Schedule 13D if they may try to influence or control the company, on 13G if they're a passive investor, and update it as the stake changes. Each holder's latest filing, from 19 Dec 2024 on; percentages are of the share class, as the holder worked them out.
| Holder | Stake |
|---|---|
| BlackRock, Inc. 13G · institution +1.1 pts · filed 2026-10-27 | 7.9% |
| STATE STREET CORP 13G · institution new · filed 2026-08-07 | 7.0% |
| VANGUARD CAPITAL MANAGEMENT LLC 13G · institution new · filed 2026-07-31 | 5.2% |
Fell to 5% or below in the last year: VANGUARD GROUP INC (0.0%, 2026-03-27; now reported by VANGUARD CAPITAL MANAGEMENT LLC), Anson Funds Management LP (4.9%, 2026-02-17), HIGHBRIDGE CAPITAL MANAGEMENT LLC (3.7%, 2026-01-30)
Insider purchases and sales since 1 Apr 2026
Shares bought or sold by the company's own officers, directors and 10% owners, in the open market or privately, as they reported to the SEC on Form 4 (due within two business days of the trade). Grants, option exercises, shares withheld for tax and gifts aren't included.
Officers and directors buying vs selling
Number of people, by quarter (10% owners not included)
Numbers
| Quarter | Buying | Bought | Selling | Sold | Sold under a plan |
|---|---|---|---|---|---|
| Q4 2024 | 0 | — | 0 | — | — |
| Q1 2025 | 0 | — | 0 | — | — |
| Q2 2025 | 3 | $84.6k | 0 | — | — |
| Q3 2025 | 0 | — | 0 | — | — |
| Q4 2025 | 1 | $100.8k | 0 | — | — |
| Q1 2026 | 0 | — | 0 | — | — |
| Q2 2026 | 0 | — | 0 | — | — |
| Q3 2026 | 0 | — | 0 | — | — |
None reported since 1 Apr 2026.
Holders, Q2 2026
| Manager | Shares | Change |
|---|---|---|
| BlackRock, Inc. 0.00% of their portfolio | 15.1m $222.4m | Added +2.9m |
| STATE STREET CORP 0.01% of their portfolio | 13.0m $191.8m | Added +4.6m |
| VANGUARD CAPITAL MANAGEMENT LLC 0.00% of their portfolio | 8.2m $121.4m | Added +700.2k |
| GEODE CAPITAL MANAGEMENT, LLC 0.00% of their portfolio | 4.9m $72.1m | Added +971.6k |
| Anson Funds Management LP 6.05% of their portfolio | 4.5m $66.4m | New |
| JONES FINANCIAL COMPANIES LLLP 0.01% of their portfolio | 2.3m $28.6m | Added +629.5k |
| VANGUARD PORTFOLIO MANAGEMENT LLC 0.00% of their portfolio | 2.2m $31.9m | Added +698.3k |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP 0.03% of their portfolio | 2.1m $30.3m | Added +1.7m |
| NORTHERN TRUST CORP 0.00% of their portfolio | 1.6m $23.9m | Added +343.9k |
| VANGUARD FIDUCIARY TRUST CO 0.00% of their portfolio | 1.3m $19.7m | Added +132.3k |
| UBS Group AG 0.00% of their portfolio | 1.3m $18.5m | Added +507.3k |
| MORGAN STANLEY 0.00% of their portfolio | 1.2m $18.2m | Reduced -100.0k |
| DAGCO, INC. 3.36% of their portfolio | 1.2m $18.2m | Added +203.7k |
| BNP PARIBAS FINANCIAL MARKETS 0.01% of their portfolio | 1.1m $15.8m | Added +1.0m |
| BANK OF AMERICA CORP /DE/ 0.00% of their portfolio | 787.9k $11.6m | Added +146.3k |
| WELLINGTON MANAGEMENT GROUP LLP 0.00% of their portfolio | 597.3k $8.8m | Added +252.5k |
| GOLDMAN SACHS GROUP INC 0.00% of their portfolio | 585.0k $8.6m | Added +29.1k |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC 0.00% of their portfolio | 565.0k $8.3m | Added +84.4k |
| Bank of New York Mellon Corp 0.00% of their portfolio | 530.0k $7.8m | Added +51.7k |
| JANE STREET GROUP, LLC 0.00% of their portfolio | 508.4k $7.5m | New |
| Nuveen, LLC 0.00% of their portfolio | 418.7k $6.2m | Reduced -252.2k |
| Opus Capital Group, LLC 0.55% of their portfolio | 385.6k $5.7m | Added +39.2k |
| Invesco Ltd. 0.00% of their portfolio | 375.3k $5.5m | Reduced -322.7k |
| Swiss National Bank 0.00% of their portfolio | 360.4k $5.3m | New |
| XTX Topco Ltd 0.07% of their portfolio | 359.1k $5.3m | New |
| WELLS FARGO & COMPANY/MN 0.00% of their portfolio | 328.8k $4.9m | Added +103.1k |
| CITIGROUP INC 0.00% of their portfolio | 326.6k $4.8m | Added +300.9k |
| RENAISSANCE TECHNOLOGIES LLC 0.01% of their portfolio | 310.4k $4.6m | New |
| Everhart Financial Group, Inc. 0.27% of their portfolio | 288.0k $4.3m | Reduced -76.4k |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC 0.00% of their portfolio | 273.4k $4.0m | New |
| Rafferty Asset Management, LLC 0.01% of their portfolio | 239.9k $3.5m | Reduced -9.5k |
| ALLIANCEBERNSTEIN L.P. 0.00% of their portfolio | 236.1k $998.5k | Added +72.1k |
| RHUMBLINE ADVISERS 0.00% of their portfolio | 230.4k $3.4m | Added +36.2k |
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM 0.00% of their portfolio | 202.4k $3.0m | Added +193.0k |
| Jefferies Financial Group Inc. 0.03% of their portfolio | 200.5k $3.0m | New |
| Mariner, LLC 0.00% of their portfolio | 198.2k $2.9m | Added +24.6k |
| DEUTSCHE BANK AG\ 0.00% of their portfolio | 190.1k $2.8m | Added +52.5k |
| ALPS ADVISORS INC 0.01% of their portfolio | 188.1k $2.8m | New |
| Legal & General Group Plc 0.00% of their portfolio | 167.8k $2.5m | Added +152.7k |
| LPL Financial LLC 0.00% of their portfolio | 155.7k $2.3m | Added +18.5k |
| PRICE T ROWE ASSOCIATES INC /MD/ 0.00% of their portfolio | 155.1k $2.3m | Added +32.9k |
| SIMPLEX TRADING, LLC 0.06% of their portfolio | 154.1k $2.3m | Reduced -141.1k |
| Vontobel Holding Ltd. 0.01% of their portfolio | 146.8k $2.2m | Reduced -27.4k |
| Vanguard Global Advisers, LLC 0.00% of their portfolio | 130.0k $1.9m | Added +1.9k |
| Tidal Investments LLC 0.00% of their portfolio | 128.8k $1.9m | Added +38.8k |
| VANGUARD ASSET MANAGEMENT, Ltd 0.00% of their portfolio | 126.0k $1.9m | New |
| PROFUND ADVISORS LLC 0.05% of their portfolio | 120.6k $1.8m | Added +8.8k |
| FRANKLIN RESOURCES INC 0.00% of their portfolio | 119.2k $1.8m | New |
| MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. 0.00% of their portfolio | 114.8k $1.7m | Added +16.5k |
| MetLife Investment Management, LLC 0.01% of their portfolio | 110.1k $1.6m | Added +15.8k |
| Daiwa Securities Group Inc. 0.00% of their portfolio | 102.5k $1.5m | Added +100.3k |
| JPMORGAN CHASE & CO 0.00% of their portfolio | 100.1k $1.5m | Added +18.3k |
| HIGHBRIDGE CAPITAL MANAGEMENT LLC 0.05% of their portfolio | 99.4k $1.5m | New |
| GSA CAPITAL PARTNERS LLP 0.09% of their portfolio | 96.4k $1.4m | Reduced -66.9k |
| STATE OF WISCONSIN INVESTMENT BOARD 0.00% of their portfolio | 95.2k $1.4m | New |
| Harvest Investment Services, LLC 0.22% of their portfolio | 94.5k $1.4m | New |
| Zurcher Kantonalbank (Zurich Cantonalbank) 0.00% of their portfolio | 83.3k $1.2m | New |
| Jupiter Topco LLC 0.00% of their portfolio | 79.6k $1.2m | First filing |
| Gotham Asset Management, LLC 0.00% of their portfolio | 74.3k $1.1m | New |
| FULCRUM WEALTH ADVISORS, LLC 0.83% of their portfolio | 73.3k $1.1m | Reduced -36.0k |
| Russell Investments Group, Ltd. 0.00% of their portfolio | 71.2k $1.1m | Added +53.2k |
| Creative Planning 0.00% of their portfolio | 70.6k $1.0m | Added +30.1k |
| NEW YORK STATE COMMON RETIREMENT FUND 0.00% of their portfolio | 66.3k $978.6k | Added +27.3k |
| NATIONAL BANK OF CANADA /FI/ 0.00% of their portfolio | 60.4k $892.1k | Added +58.1k |
| OSAIC HOLDINGS, INC. 0.00% of their portfolio | 60.3k $889.8k | Added +13.0k |
| FIFTH THIRD BANCORP 0.00% of their portfolio | 60.2k $888.4k | Added +383 |
| AQR CAPITAL MANAGEMENT LLC 0.00% of their portfolio | 58.1k $857.9k | Added +4.1k |
| State of New Jersey Common Pension Fund D 0.00% of their portfolio | 58.1k $857.1k | New |
| Police & Firemen's Retirement System of New Jersey 0.01% of their portfolio | 55.7k $821.6k | Added +8.6k |
| ARIZONA STATE RETIREMENT SYSTEM 0.00% of their portfolio | 49.6k $731.4k | New |
| Caption Management, LLC 0.03% of their portfolio | 49.4k $728.7k | New |
| MANUFACTURERS LIFE INSURANCE COMPANY, THE 0.00% of their portfolio | 48.9k $722.3k | Added +3.2k |
| MERCER GLOBAL ADVISORS INC /ADV 0.00% of their portfolio | 48.4k $714.1k | New |
| Accurate Wealth Management, LLC 0.06% of their portfolio | 47.5k $614.7k | Added +14.9k |
| Vanguard Investments Australia, Ltd. 0.00% of their portfolio | 46.4k $684.6k | New |
| COMMONWEALTH EQUITY SERVICES, LLC 0.00% of their portfolio | 45.1k $665.5k | Added +6.6k |
| NORTHSTAR ASSET MANAGEMENT Co 0.10% of their portfolio | 45.0k $509.4k | Reduced -5.0k |
| INSTRUMENTAL WEALTH, LLC 0.34% of their portfolio | 44.9k $662.9k | Unchanged |
| Virtus Investment Advisers, LLC 0.14% of their portfolio | 41.8k $616.8k | New |
| AXXCESS WEALTH MANAGEMENT, LLC 0.01% of their portfolio | 41.4k $610.7k | Added +6.0k |
| KLP KAPITALFORVALTNING AS 0.00% of their portfolio | 40.7k $600.7k | New |
| SJS Investment Consulting Inc. 0.06% of their portfolio | 40.0k $590.4k | Added +15.0k |
| Wealthfront Advisers LLC 0.00% of their portfolio | 39.8k $587.8k | Added +28.4k |
| VOYA INVESTMENT MANAGEMENT LLC 0.00% of their portfolio | 37.3k $550.5k | Added +8.0k |
| Quantinno Capital Management LP 0.00% of their portfolio | 37.0k $546.7k | Reduced -37.3k |
| Visionary Horizons, LLC 0.22% of their portfolio | 36.0k $531.4k | Unchanged |
| BARCLAYS PLC 0.00% of their portfolio | 35.8k $528.2k | Added +3.4k |
| Kestra Advisory Services, LLC 0.00% of their portfolio | 35.0k $516.3k | Added +5.8k |
| MANGROVE PARTNERS IM, LLC 0.03% of their portfolio | 34.1k $503.9k | New |
| E Fund Management Co., Ltd. 0.01% of their portfolio | 33.8k $499.3k | Added +2.5k |
| Cambridge Investment Research Advisors, Inc. 0.00% of their portfolio | 32.3k $478.0k | Added +19.9k |
| INTECH INVESTMENT MANAGEMENT LLC 0.00% of their portfolio | 32.2k $475.0k | Reduced -19.1k |
| Scissortail Wealth Management, LLC 0.09% of their portfolio | 31.3k $462.3k | Added +4.0k |
| PRUDENTIAL FINANCIAL INC 0.00% of their portfolio | 31.1k $459.2k | Added +2.4k |
| Sculptor Capital LP 0.00% of their portfolio | 30.3k $447.2k | New |
| Walleye Capital LLC 0.00% of their portfolio | 30.1k $444.5k | New |
| Genesee Capital Advisors, LLC 0.14% of their portfolio | 30.0k $442.8k | Unchanged |
| Walleye Trading LLC 0.01% of their portfolio | 29.0k $427.5k | New |
| SEI INVESTMENTS CO 0.00% of their portfolio | 26.6k $392.3k | Unchanged |
| STRS OHIO 0.00% of their portfolio | 26.1k $385.2k | New |