ZENAS BIOPHARMA INC (ZBIO)
Institutional ownership reported to the SEC as of Q2 2026, across 15 quarters.
Institutions report 61,266,991 shares against 65,176,723 outstanding. Shares only - option lines are excluded, which is why this can be compared with the company at all. The count comes from the cover page of the company's own most recent report, so it is dated when that was filed rather than at quarter end. A figure this high can overstate: where an adviser and a sub-adviser both report the same shares, both are counted.
Calls and puts are the parts of reported value carried in derivative lines rather than shares, and they point in opposite directions: a manager holding calls is positioned for the security, one holding puts against it - or hedging shares they already own, which is why index funds carry so many. Most sites add the two together and report one figure, which averages away the only interesting part.
Holders
| Filer | Value | Shares | Their book | Held | Change |
|---|---|---|---|---|---|
| FMR LLC | $241.3M | 9,506,701 | 0.01% | 8q | +4.7%+$10.8M |
| SR One Capital Management, LP | $127.9M | 5,037,854 | 12.31% | 8q | HELD |
| NEA Management Company, LLC | $102.1M | 4,023,219 | 6.43% | 8q | HELD |
| ENAVATE SCIENCES GP, LLC | $99.5M | 3,919,159 | 28.80% | 7q | HELD |
| FEDERATED HERMES, INC. | $79.1M | 3,116,805 | 0.11% | 8q | HELD |
| BlackRock, Inc. | $68.2M | 2,686,225 | 0.00% | 7q | +31.8%+$16.5M |
| Capital International Investors | $63.5M | 2,502,912 | 0.01% | 2q | +2.8%+$1.7M |
| Polar Capital Holdings Plc | $61.2M | 2,412,772 | 0.14% | 3q | -5.3%-$3.4M |
| Royalty Pharma Sub-Manager, LLC | $60.6M | 2,388,150 | 25.05% | 3q | HELD |
| Fairmount Funds Management LLC | $59.9M | 2,359,025 | 3.96% | 8q | HELD |
| STATE STREET CORP | $52.2M | 2,055,100 | 0.00% | 7q | +39.7%+$14.8M |
| NVP ASSOCIATES, LLC | $46.7M | 1,838,482 | 14.22% | 8q | HELD |
| WELLINGTON MANAGEMENT GROUP LLP | $40.5M | 1,593,819 | 0.01% | 8q | +27.9%+$8.8M |
| VANGUARD CAPITAL MANAGEMENT LLC | $34.4M | 1,354,864 | 0.00% | 2q | +8.8%+$2.8M |
| BANK OF AMERICA CORP /DE/ | $31.2M | 1,231,159 | 0.00% | 7q | +217.0%+$21.4M |
| PRICE T ROWE ASSOCIATES INC /MD/ | $31.1M | 1,226,928 | 0.00% | 8q | +243.4%+$22.1M |
| GEODE CAPITAL MANAGEMENT, LLC | $22.4M | 882,654 | 0.00% | 8q | +34.6%+$5.8M |
| ALLIANCEBERNSTEIN L.P. | $21.6M | 1,103,388 | 0.01% | 5q | +23.0%+$4.0M |
| TWO SIGMA INVESTMENTS, LP | $20.7M | 815,150 | 0.01% | 5q | +196.4%+$13.7M |
| EcoR1 Capital, LLC | $20.0M | 789,500 | 0.97% | 3q | HELD |
| MILLENNIUM MANAGEMENT LLC | $16.8M | 660,470 | 0.01% | 4q | +38.5%+$4.7M |
| Woodline Partners LP | $15.0M | 590,539 | 0.05% | 2q | HELD |
| Balyasny Asset Management L.P. | $14.6M | 576,717 | 0.02% | 3q | -13.5%-$2.3M |
| ArrowMark Colorado Holdings LLC | $14.6M | 573,318 | 0.61% | 8q | -13.0%-$2.2M |
| SILVERARC CAPITAL MANAGEMENT, LLC | $12.9M | 509,789 | 1.34% | 2q | -55.1%-$15.9M |
| Rock Springs Capital Management LP | $12.7M | 502,077 | 0.62% | 8q | HELD |
| Pivotal bioVenture Partners Investment Advisor LLC | $12.5M | 490,766 | 4.05% | 8q | -17.1%-$2.6M |
| NEXTBio Capital Management LP | $10.8M | 426,736 | 4.98% | 3q | HELD |
| Vestal Point Capital, LP | $9.3M | 365,000 | 0.22% | 2q | +82.5%+$4.2M |
| MARSHALL WACE, LLP | $8.2M | 323,442 | 0.01% | 3q | -35.6%-$4.5M |
| JENNISON ASSOCIATES LLC | $8.0M | 314,049 | 0.00% | 2q | +25.6%+$1.6M |
| VANGUARD PORTFOLIO MANAGEMENT LLC | $7.7M | 304,870 | 0.00% | 2q | +21.3%+$1.4M |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC | $7.7M | 302,085 | 0.00% | 7q | +34.6%+$2.0M |
| NORTHERN TRUST CORP | $7.1M | 281,140 | 0.00% | 7q | +44.4%+$2.2M |
| GOLDMAN SACHS GROUP INC | $6.9M | 271,163 | 0.00% | 3q | -28.9%-$2.8M |
| VANGUARD FIDUCIARY TRUST CO | $6.5M | 254,623 | 0.00% | 2q | +41.9%+$1.9M |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | $6.2M CALL+PUT | options only | 0.00% | 6q | OPTIONS |
| SPHERA FUNDS MANAGEMENT LTD. | $5.9M | 230,834 | 0.76% | 2q | +7.7%+$418.8K |
| CITADEL ADVISORS LLC | $5.8M incl. $784.2K options CALL | 195,780 | 0.00% | 3q | +192.8%+$3.8M |
| iA Global Asset Management Inc. | $5.5M | 215,130 | 0.06% | 2q | HELD |
| Walleye Capital LLC | $5.3M | 209,050 | 0.02% | 2q | +66.9%+$2.1M |
| Sio Capital Management, LLC | $5.3M | 208,557 | 0.88% | 2q | -37.1%-$3.1M |
| UBS Group AG | $4.5M | 178,089 | 0.00% | 8q | -51.5%-$4.8M |
| Voleon Capital Management LP | $4.2M | 167,145 | 0.08% | 3q | +464.5%+$3.5M |
| BNP PARIBAS FINANCIAL MARKETS | $3.8M | 151,086 | 0.00% | 7q | +1411.0%+$3.6M |
| MORGAN STANLEY | $3.4M | 134,979 | 0.00% | 8q | +44.5%+$1.1M |
| Squarepoint Ops LLC | $3.2M | 125,185 | 0.00% | 3q | +192.0%+$2.1M |
| BARCLAYS PLC | $2.9M | 115,965 | 0.00% | 8q | +291.6%+$2.2M |
| SEVEN GRAND MANAGERS, LLC | $2.5M | 100,000 | 0.10% | 2q | HELD |
| Birchview Capital, LP | $2.4M | 93,601 | 1.11% | 2q | +33.7%+$599.0K |
| Verition Fund Management LLC | $1.9M | 72,988 | 0.01% | new | NEW |
| Bank of New York Mellon Corp | $1.8M | 70,477 | 0.00% | 7q | +15.8%+$244.0K |
| J. Goldman & Co LP | $1.7M | 68,232 | 0.04% | 2q | +85.4%+$797.8K |
| CSM Advisors, LLC | $1.7M | 67,622 | 0.04% | new | NEW |
| Nuveen, LLC | $1.7M | 66,638 | 0.00% | 6q | -1.7%-$28.7K |
| ALPS ADVISORS INC | $1.6M | 63,675 | 0.01% | 7q | +45.7%+$507.1K |
| Swiss National Bank | $1.4M | 53,200 | 0.00% | 3q | +68.4%+$548.2K |
| Exome Asset Management LLC | $1.3M | 52,443 | 0.82% | 2q | -35.0%-$717.9K |
| Jump Financial, LLC | $1.3M | 51,022 | 0.01% | 2q | -15.0%-$227.9K |
| CITIGROUP INC | $1.3M | 49,521 | 0.00% | 7q | +400.8%+$1.0M |
| LOS ANGELES CAPITAL MANAGEMENT LLC | $1.2M | 48,465 | 0.00% | new | NEW |
| XTX Topco Ltd | $1.0M | 40,034 | 0.01% | 3q | +107.3%+$525.9K |
| Burkehill Global Management, LP | $1.0M | 40,000 | 0.04% | 2q | HELD |
| JANE STREET GROUP, LLC | $989.8K CALL | options only | 0.00% | 3q | OPTIONS |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC | $959.1K | 37,790 | 0.00% | 3q | +143.4%+$565.1K |
| Rafferty Asset Management, LLC | $952.0K | 37,509 | 0.00% | 2q | -22.1%-$270.6K |
| Atom Investors LP | $942.8K | 37,149 | 0.08% | 2q | -65.3%-$1.8M |
| RHUMBLINE ADVISERS | $869.1K | 34,245 | 0.00% | 7q | +27.7%+$188.6K |
| BOOTHBAY FUND MANAGEMENT, LLC | $844.6K | 33,280 | 0.01% | new | NEW |
| AQR CAPITAL MANAGEMENT LLC | $789.3K | 31,100 | 0.00% | 5q | -39.0%-$504.3K |
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM | $748.0K | 29,471 | 0.00% | 7q | +86.3%+$346.5K |
| DEUTSCHE BANK AG\ | $733.0K | 28,881 | 0.00% | 7q | +49.9%+$244.0K |
| DCF Advisers, LLC | $715.3K | 28,184 | 0.13% | new | NEW |
| STATE OF WISCONSIN INVESTMENT BOARD | $683.3K | 26,922 | 0.00% | 3q | +29.3%+$155.0K |
| JPMORGAN CHASE & CO | $660.5K | 24,445 | 0.00% | 7q | -2.6%-$17.9K |
| WELLS FARGO & COMPANY/MN | $659.8K | 25,995 | 0.00% | 7q | +192.6%+$434.3K |
| VANGUARD ASSET MANAGEMENT, Ltd | $523.4K | 20,623 | 0.00% | 2q | +93.8%+$253.3K |
| Legal & General Group Plc | $508.2K | 20,023 | 0.00% | 7q | +91.9%+$243.4K |
| Invesco Ltd. | $481.1K | 18,954 | 0.00% | 4q | -83.3%-$2.4M |
| China Universal Asset Management Co., Ltd. | $478.4K | 18,848 | 0.03% | 3q | +39.3%+$135.1K |
| PROFUND ADVISORS LLC | $478.1K | 18,838 | 0.01% | 2q | -12.0%-$65.4K |
| ALLSTATE CORP | $463.0K | 18,241 | 0.00% | 2q | HELD |
| MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. | $442.9K | 17,423 | 0.00% | 7q | +21.1%+$77.2K |
| Y-Intercept (Hong Kong) Ltd | $439.9K | 17,332 | 0.01% | new | NEW |
| MetLife Investment Management, LLC | $432.5K | 17,041 | 0.00% | 7q | +32.0%+$104.9K |
| Virtus Investment Advisers, LLC | $419.4K | 16,525 | 0.10% | 3q | +146.0%+$248.9K |
| Point72 Asset Management, L.P. | $409.5K | 16,136 | 0.00% | new | NEW |
| Vanguard Global Advisers, LLC | $389.1K | 15,332 | 0.00% | 2q | -26.4%-$139.8K |
| NORDEA INVESTMENT MANAGEMENT AB | $382.9K | 15,050 | 0.00% | new | NEW |
| Brevan Howard Capital Management LP | $372.4K | 14,674 | 0.00% | new | NEW |
| Engineers Gate Manager LP | $329.4K | 12,980 | 0.00% | new | NEW |
| Russell Investments Group, Ltd. | $323.3K | 12,740 | 0.00% | 4q | +368.2%+$254.3K |
| Creative Planning | $297.5K | 11,723 | 0.00% | 4q | -7.4%-$23.7K |
| VARCOV Co. | $266.6K | 10,505 | 0.10% | new | NEW |
| NEW YORK STATE COMMON RETIREMENT FUND | $261.4K | 10,300 | 0.00% | 6q | +66.1%+$104.1K |
| MASSACHUSETTS FINANCIAL SERVICES CO /MA/ | $229.8K | 9,053 | 0.00% | new | NEW |
| Scientech Research LLC | $229.1K | 9,028 | 0.19% | 2q | -30.3%-$99.6K |
| DIMENSIONAL FUND ADVISORS LP | $225.2K | 8,874 | 0.00% | new | NEW |
| HRT FINANCIAL LP | $225.0K | 8,879 | 0.00% | 2q | -65.5%-$427.5K |
| Quantinno Capital Management LP | $217.8K | 8,581 | 0.00% | 2q | -59.4%-$318.4K |
Five percent filings
Anyone crossing 5% of a company must say so within days - far sooner than the next quarterly holdings report. A 13D declares an intent to influence the company; a 13G is the passive version. See all activist filings →
| Filed | Form | Filer | % of class |
|---|---|---|---|
| 2026-10-27 | 13G | BlackRock, Inc. | 5.0% |
What the company announced
Form 8-K filings from the last 120 days, showing only the items worth a reader's attention. Earnings releases, exhibit attachments and general disclosures are filed constantly and are left out. Filed is when the SEC received it; event is the date the company says the thing happened.
| Filed | Event date | What | Source |
|---|---|---|---|
| 2026-08-13 | 2026-08-12 | Directors or officers departed or appointed | filing |
What the insiders did
Open market purchases and sales reported on Form 4 in the last 180 days. Grants, option exercises and shares surrendered to cover tax are left out: they are compensation rather than a decision to buy or sell. Where a broker filled one order in tranches the lines are summed, because it was one decision.
Officers and directors
| Date | Insider | Role | Side | Shares | Value |
|---|---|---|---|---|---|
| 2026-05-18 | MOULDER LEON O JR | Chief Executive Officer | Bought | 60,000 | $1.0M |
Quarter by quarter
Coverage begins with the quarter ending 2018-12-31. Earlier filings exist only as occasional late amendments, too sparse to describe a market, so they are not shown.
| Quarter | Holders | Value | Shares | New | Added | Trimmed | Options |
|---|---|---|---|---|---|---|---|
| Q3 2026 | 20 | $2.5M | 92,057 | 5 | 7 | 3 | 0.0% |
| Q2 2026 | 147 | $1.6B | 61,266,991 | 27 | 60 | 38 | 0.5% |
| Q1 2026 | 141 | $1.2B | 57,784,846 | 45 | 58 | 17 | 0.5% |
| Q4 2025 | 127 | $1.6B | 42,824,517 | 48 | 37 | 22 | 1.0% |
| Q3 2025 | 81 | $774.9M | 34,832,289 | 14 | 22 | 20 | 0.0% |
| Q2 2025 | 73 | $330.0M | 34,056,527 | 10 | 33 | 11 | 0.0% |
| Q1 2025 | 67 | $256.7M | 32,489,866 | 12 | 14 | 20 | 0.0% |
| Q4 2024 | 65 | $259.8M | 31,716,256 | 30 | 13 | 7 | 0.0% |
| Q3 2024 | 44 | $418.5M | 24,771,152 | 43 | 0 | 0 | 0.0% |
| Q1 2020 | 1 | $9.0K | 1,026 | 1 | 0 | 0 | 0.0% |
| Q4 2019 | 5 | $441.0K | 48,275 | 0 | 3 | 2 | 0.0% |
| Q3 2019 | 5 | $596.0K | 35,406 | 1 | 1 | 3 | 0.0% |
| Q2 2019 | 5 | $740.0K | 55,014 | 2 | 1 | 2 | 0.0% |
| Q1 2019 | 6 | $856.0K | 52,783 | 1 | 1 | 3 | 18.1% |
| Q4 2018 | 6 | $1.3M | 49,078 | 2 | 0 | 0 | 19.5% |
