Who owns Zenas BioPharma (ZBIO)
Which tracked institutional funds hold ZBIO, how they are positioned, and who is buying versus exiting — from SEC Form 13F-HR filings. See ZBIO 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 ZBIO is one-sided between 2026-Q1 and 2026-Q2: 63 added or opened and 20 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
ZBIO’s largest tracked holder by dollar value, FMR LLC, 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 ZBIO 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 139 tracked filers holding ZBIO, 87 increased or opened the position and 64 reduced or closed it; over the same quarter, open-market insider Form 4s were net purchases.
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 ZBIO 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 4
- Verition Fund Management LLC$2M
- LOS ANGELES CAPITAL MANAGEMENT LLC$1M
- BOOTHBAY FUND MANAGEMENT, LLC$845K
- DCF Advisers, LLC$715K
Full exits 12
- GREAT POINT PARTNERS LLC$10M
- Jefferies Financial Group Inc.$4M
- iA Global Asset Management Inc.$4M
- SEB Asset Management AB$3M
- Monashee Investment Management LLC$3M
- Maven Securities LTD$3M
Largest adds
- FMR LLC$64M
- SR One Capital Management, LP$29M
- BlackRock, Inc.$28M
- PRICE T ROWE ASSOCIATES INC /MD/$24M
- BANK OF AMERICA CORP /DE/$24M
- NEA Management Company, LLC$23M
Largest trims
- ALLIANCEBERNSTEIN L.P.$11M
- SILVERARC CAPITAL MANAGEMENT, LLC$9M
- UBS Group AG$3M
- Invesco Ltd.$2M
- MARSHALL WACE, LLP$2M
- Sio Capital Management, LLC$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 |
|---|---|---|---|---|
| FMR LLC added | 9,506,701 | $241M | 15.7% | 2026-Q2 |
| SR One Capital Management, LP | 5,037,854 | $128M | 8.3% | 2026-Q2 |
| NEA Management Company, LLC | 4,023,219 | $102M | 6.6% | 2026-Q2 |
| ENAVATE SCIENCES GP, LLC | 3,919,159 | $99M | 6.5% | 2026-Q2 |
| FEDERATED HERMES, INC. trimmed | 3,116,805 | $79M | 5.1% | 2026-Q2 |
| BlackRock, Inc. added | 2,686,225 | $68M | 4.4% | 2026-Q2 |
| Capital International Investors added | 2,502,912 | $64M | 4.1% | 2026-Q2 |
| Polar Capital Holdings Plc trimmed | 2,412,772 | $61M | 4.0% | 2026-Q2 |
| Royalty Pharma Sub-Manager, LLC | 2,388,150 | $61M | 3.9% | 2026-Q2 |
| Fairmount Funds Management LLC | 2,359,025 | $60M | 3.9% | 2026-Q2 |
| STATE STREET CORP added | 2,055,100 | $52M | 3.4% | 2026-Q2 |
| NVP ASSOCIATES, LLC | 1,838,482 | $47M | 3.0% | 2026-Q2 |
| WELLINGTON MANAGEMENT GROUP LLP added | 1,593,819 | $40M | 2.6% | 2026-Q2 |
| VANGUARD CAPITAL MANAGEMENT LLC added | 1,354,864 | $34M | 2.2% | 2026-Q2 |
| BANK OF AMERICA CORP /DE/ added | 1,231,159 | $31M | 2.0% | 2026-Q2 |
| PRICE T ROWE ASSOCIATES INC /MD/ added | 1,226,928 | $31M | 2.0% | 2026-Q2 |
| ALLIANCEBERNSTEIN L.P. added | 1,103,388 | $22M | 1.4% | 2026-Q2 |
| GEODE CAPITAL MANAGEMENT, LLC added | 882,654 | $22M | 1.5% | 2026-Q2 |
| TWO SIGMA INVESTMENTS, LP added | 815,150 | $21M | 1.3% | 2026-Q2 |
| EcoR1 Capital, LLC | 789,500 | $20M | 1.3% | 2026-Q2 |
| MILLENNIUM MANAGEMENT LLC added | 660,470 | $17M | 1.1% | 2026-Q2 |
| Woodline Partners LP added | 590,539 | $15M | 1.0% | 2026-Q2 |
| BALYASNY ASSET MANAGEMENT L.P. trimmed | 576,717 | $15M | 1.0% | 2026-Q2 |
| ArrowMark Colorado Holdings LLC trimmed | 573,318 | $15M | 0.9% | 2026-Q2 |
| SILVERARC CAPITAL MANAGEMENT, LLC trimmed | 509,789 | $13M | 0.8% | 2026-Q2 |
| Rock Springs Capital Management LP | 502,077 | $13M | 0.8% | 2026-Q2 |
| Pivotal bioVenture Partners Investment Advisor LLC trimmed | 490,766 | $12M | 0.8% | 2026-Q2 |
| NEXTBio Capital Management LP | 426,736 | $11M | 0.7% | 2026-Q2 |
| Vestal Point Capital, LP added | 365,000 | $9M | 0.6% | 2026-Q2 |
| MARSHALL WACE, LLP trimmed | 323,442 | $8M | 0.5% | 2026-Q2 |
| JENNISON ASSOCIATES LLC added | 314,049 | $8M | 0.5% | 2026-Q2 |
| VANGUARD PORTFOLIO MANAGEMENT LLC added | 304,870 | $8M | 0.5% | 2026-Q2 |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC added | 302,085 | $8M | 0.5% | 2026-Q2 |
| NORTHERN TRUST CORP added | 281,140 | $7M | 0.5% | 2026-Q2 |
| GOLDMAN SACHS GROUP INC trimmed | 271,163 | $7M | 0.4% | 2026-Q2 |
| VANGUARD FIDUCIARY TRUST CO added | 254,623 | $6M | 0.4% | 2026-Q2 |
| SPHERA FUNDS MANAGEMENT LTD. added | 230,834 | $6M | 0.4% | 2026-Q2 |
| Walleye Capital LLC added | 209,050 | $5M | 0.3% | 2026-Q2 |
| Sio Capital Management, LLC trimmed | 208,557 | $5M | 0.3% | 2026-Q2 |
| CITADEL ADVISORS LLC added | 195,780 | $5M | 0.3% | 2026-Q2 |
| UBS Group AG trimmed | 178,089 | $5M | 0.3% | 2026-Q2 |
| Voleon Capital Management LP added | 167,145 | $4M | 0.3% | 2026-Q2 |
| BNP PARIBAS FINANCIAL MARKETS added | 151,086 | $4M | 0.2% | 2026-Q2 |
| MORGAN STANLEY added | 134,979 | $3M | 0.2% | 2026-Q2 |
| Squarepoint Ops LLC added | 125,185 | $3M | 0.2% | 2026-Q2 |
| BARCLAYS PLC added | 115,965 | $3M | 0.2% | 2026-Q2 |
| SEVEN GRAND MANAGERS, LLC | 100,000 | $3M | 0.2% | 2026-Q2 |
| Birchview Capital, LP added | 93,601 | $2M | 0.2% | 2026-Q2 |
| Verition Fund Management LLC new | 72,988 | $2M | 0.1% | 2026-Q2 |
| Bank of New York Mellon Corp added | 70,477 | $2M | 0.1% | 2026-Q2 |
| J. Goldman & Co LP added | 68,232 | $2M | 0.1% | 2026-Q2 |
| Nuveen, LLC trimmed | 66,638 | $2M | 0.1% | 2026-Q2 |
| ALPS ADVISORS INC added | 63,675 | $2M | 0.1% | 2026-Q2 |
| Swiss National Bank added | 53,200 | $1M | 0.1% | 2026-Q2 |
| Exome Asset Management LLC trimmed | 52,443 | $1M | 0.1% | 2026-Q2 |
| Jump Financial, LLC trimmed | 51,022 | $1M | 0.1% | 2026-Q2 |
| CITIGROUP INC added | 49,521 | $1M | 0.1% | 2026-Q2 |
| LOS ANGELES CAPITAL MANAGEMENT LLC added | 48,465 | $1M | 0.1% | 2026-Q2 |
| XTX Topco Ltd added | 40,034 | $1M | 0.1% | 2026-Q2 |
| Burkehill Global Management, LP | 40,000 | $1M | 0.1% | 2026-Q2 |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC added | 37,790 | $959K | 0.1% | 2026-Q2 |
| Rafferty Asset Management, LLC trimmed | 37,509 | $952K | 0.1% | 2026-Q2 |
| Atom Investors LP trimmed | 37,149 | $943K | 0.1% | 2026-Q2 |
| RHUMBLINE ADVISERS added | 34,245 | $869K | 0.1% | 2026-Q2 |
| BOOTHBAY FUND MANAGEMENT, LLC new | 33,280 | $845K | 0.1% | 2026-Q2 |
| AQR CAPITAL MANAGEMENT LLC trimmed | 31,100 | $789K | 0.1% | 2026-Q2 |
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM added | 29,471 | $748K | 0.0% | 2026-Q2 |
| DEUTSCHE BANK AG\ added | 28,881 | $733K | 0.0% | 2026-Q2 |
| DCF Advisers, LLC new | 28,184 | $715K | 0.0% | 2026-Q2 |
| STATE OF WISCONSIN INVESTMENT BOARD added | 26,922 | $683K | 0.0% | 2026-Q2 |
| WELLS FARGO & COMPANY/MN added | 25,995 | $660K | 0.0% | 2026-Q2 |
| JPMORGAN CHASE & CO trimmed | 24,445 | $661K | 0.0% | 2026-Q2 |
| VANGUARD ASSET MANAGEMENT, Ltd added | 20,623 | $523K | 0.0% | 2026-Q2 |
| Legal & General Group Plc added | 20,023 | $508K | 0.0% | 2026-Q2 |
| Invesco Ltd. trimmed | 18,954 | $481K | 0.0% | 2026-Q2 |
| China Universal Asset Management Co., Ltd. added | 18,848 | $478K | 0.0% | 2026-Q2 |
| PROFUND ADVISORS LLC trimmed | 18,838 | $478K | 0.0% | 2026-Q2 |
| ALLSTATE CORP added | 18,241 | $463K | 0.0% | 2026-Q2 |
| MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. added | 17,423 | $443K | 0.0% | 2026-Q2 |
| Y-Intercept (Hong Kong) Ltd new | 17,332 | $440K | 0.0% | 2026-Q2 |
| MetLife Investment Management, LLC added | 17,041 | $433K | 0.0% | 2026-Q2 |
| Virtus Investment Advisers, LLC added | 16,525 | $419K | 0.0% | 2026-Q2 |
| Point72 Asset Management, L.P. trimmed | 16,136 | $410K | 0.0% | 2026-Q2 |
| Vanguard Global Advisers, LLC trimmed | 15,332 | $389K | 0.0% | 2026-Q2 |
| NORDEA INVESTMENT MANAGEMENT AB new | 15,050 | $383K | 0.0% | 2026-Q2 |
| Brevan Howard Capital Management LP added | 14,674 | $372K | 0.0% | 2026-Q2 |
| Engineers Gate Manager LP new | 12,980 | $329K | 0.0% | 2026-Q2 |
| Russell Investments Group, Ltd. added | 12,740 | $323K | 0.0% | 2026-Q2 |
| Creative Planning trimmed | 11,723 | $298K | 0.0% | 2026-Q2 |
| VARCOV Co. added | 10,505 | $267K | 0.0% | 2026-Q2 |
| NEW YORK STATE COMMON RETIREMENT FUND added | 10,300 | $261K | 0.0% | 2026-Q2 |
| MASSACHUSETTS FINANCIAL SERVICES CO /MA/ new | 9,053 | $230K | 0.0% | 2026-Q2 |
| Scientech Research LLC trimmed | 9,028 | $229K | 0.0% | 2026-Q2 |
| DIMENSIONAL FUND ADVISORS LP new | 8,874 | $225K | 0.0% | 2026-Q2 |
| Quantinno Capital Management LP trimmed | 8,581 | $218K | 0.0% | 2026-Q2 |
| State of New Jersey Common Pension Fund D new | 8,571 | $218K | 0.0% | 2026-Q2 |
| Police & Firemen's Retirement System of New Jersey added | 8,418 | $214K | 0.0% | 2026-Q2 |
| MANUFACTURERS LIFE INSURANCE COMPANY, THE added | 8,032 | $204K | 0.0% | 2026-Q2 |
| Jupiter Topco LLC new | 7,900 | $201K | 0.0% | 2026-Q2 |
| Zurcher Kantonalbank (Zurich Cantonalbank) added | 7,563 | $192K | 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.