Who owns CBIO (CBIO)
Which tracked institutional funds hold CBIO, how they are positioned, and who is buying versus exiting — from SEC Form 13F-HR filings. See CBIO company fundamentals →
Ownership as of the 2026-Q1 13F filings. 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 CBIO is one-sided between 2025-Q4 and 2026-Q1: 38 added or opened and 9 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
CBIO’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 CBIO 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 2025-Q4 and 2026-Q1, across 60 tracked filers holding CBIO, 34 increased or opened the position and 21 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 CBIO between the 2025-Q4 and 2026-Q1 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 7
- VANGUARD CAPITAL MANAGEMENT LLC$15M
- Exome Asset Management LLC$3M
- JENNISON ASSOCIATES LLC$3M
- SILVERARC CAPITAL MANAGEMENT, LLC$2M
- Hudson Bay Capital Management LP$2M
- VANGUARD FIDUCIARY TRUST CO$908K
Full exits 7
- VANGUARD GROUP INC$7M
- Boxer Capital Management, LLC$5M
- Driehaus Capital Management LLC$4M
- HEIGHTS CAPITAL MANAGEMENT, INC$3M
- WELLINGTON MANAGEMENT GROUP LLP$2M
- Blackstone Inc.$897K
Largest adds
- FMR LLC$27M
- BALYASNY ASSET MANAGEMENT L.P.$26M
- BVF INC/IL$18M
- Fairmount Funds Management LLC$18M
- Venrock Adviser, LLC$14M
- TANG CAPITAL MANAGEMENT LLC$11M
Largest trims
- ADAR1 Capital Management, LLC$6M
- PERCEPTIVE ADVISORS LLC$2M
Institutional holders
One row per tracked fund, largest reported value first. “% of value” is the fund’s share of this security’s tracked institutional value — not of shares outstanding. Rows marked stale are from an earlier filing than the security’s latest quarter — that fund is absent from the newest snapshot (position exited, or reported under a different name).
| Fund | Shares | Reported value | % of value | Quarter |
|---|---|---|---|---|
| FMR LLC | 4,133,514 | $76M | 14.8% | 2026-Q1 |
| BVF INC/IL | 2,748,763 | $50M | 9.9% | 2026-Q1 |
| Fairmount Funds Management LLC | 2,747,866 | $50M | 9.8% | 2026-Q1 |
| Venrock Adviser, LLC | 2,133,576 | $39M | 7.6% | 2026-Q1 |
| FCPM III SERVICES B.V. | 1,677,852 | $31M | 6.0% | 2026-Q1 |
| BALYASNY ASSET MANAGEMENT L.P. added | 1,510,033 | $28M | 5.4% | 2026-Q1 |
| Vestal Point Capital, LP | 1,500,000 | $28M | 5.4% | 2026-Q1 |
| Opaleye Management Inc. added | 1,312,615 | $24M | 4.7% | 2026-Q1 |
| TANG CAPITAL MANAGEMENT LLC added | 1,160,000 | $21M | 4.2% | 2026-Q1 |
| VANGUARD CAPITAL MANAGEMENT LLC new | 801,395 | $15M | 2.9% | 2026-Q1 |
| Logos Global Management LP trimmed | 482,500 | $9M | 1.7% | 2026-Q1 |
| Deep Track Capital, LP | 453,686 | $8M | 1.6% | 2026-Q1 |
| NEXTBio Capital Management LP | 372,856 | $7M | 1.3% | 2026-Q1 |
| RTW INVESTMENTS, LP | 372,856 | $7M | 1.3% | 2026-Q1 |
| MILLENNIUM MANAGEMENT LLC added | 323,553 | $6M | 1.2% | 2026-Q1 |
| PRICE T ROWE ASSOCIATES INC /MD/ trimmed | 303,551 | $6M | 1.1% | 2026-Q1 |
| Point72 Asset Management, L.P. | 300,000 | $6M | 1.1% | 2026-Q1 |
| Alyeska Investment Group, L.P. | 264,000 | $5M | 0.9% | 2026-Q1 |
| GOLDMAN SACHS GROUP INC added | 228,475 | $4M | 0.8% | 2026-Q1 |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP added | 213,635 | $4M | 0.8% | 2026-Q1 |
| PERCEPTIVE ADVISORS LLC trimmed | 206,942 | $4M | 0.7% | 2026-Q1 |
| MARSHALL WACE, LLP added | 200,780 | $4M | 0.7% | 2026-Q1 |
| Exome Asset Management LLC new | 153,191 | $3M | 0.5% | 2026-Q1 |
| JENNISON ASSOCIATES LLC new | 152,974 | $3M | 0.5% | 2026-Q1 |
| SILVERARC CAPITAL MANAGEMENT, LLC new | 130,500 | $2M | 0.5% | 2026-Q1 |
| TWO SIGMA INVESTMENTS, LP trimmed | 115,828 | $2M | 0.4% | 2026-Q1 |
| BlackRock, Inc. added | 115,725 | $2M | 0.4% | 2026-Q1 |
| GEODE CAPITAL MANAGEMENT, LLC added | 104,221 | $2M | 0.4% | 2026-Q1 |
| Hudson Bay Capital Management LP new | 88,867 | $2M | 0.3% | 2026-Q1 |
| Stonepine Capital Management, LLC trimmed | 85,000 | $2M | 0.3% | 2026-Q1 |
| UBS Group AG added | 82,706 | $2M | 0.3% | 2026-Q1 |
| Woodline Partners LP | 74,000 | $1M | 0.3% | 2026-Q1 |
| Burkehill Global Management, LP | 74,000 | $1M | 0.3% | 2026-Q1 |
| ADAR1 Capital Management, LLC trimmed | 50,273 | $924K | 0.2% | 2026-Q1 |
| VANGUARD FIDUCIARY TRUST CO new | 49,423 | $908K | 0.2% | 2026-Q1 |
| STATE STREET CORP added | 39,067 | $718K | 0.1% | 2026-Q1 |
| JPMORGAN CHASE & CO added | 41,004 | $681K | 0.1% | 2026-Q1 |
| BARCLAYS PLC added | 30,189 | $555K | 0.1% | 2026-Q1 |
| BANK OF AMERICA CORP /DE/ added | 29,277 | $538K | 0.1% | 2026-Q1 |
| MOORE CAPITAL MANAGEMENT, LP | 25,000 | $459K | 0.1% | 2026-Q1 |
| Lighthouse Investment Partners, LLC new | 25,000 | $459K | 0.1% | 2026-Q1 |
| MANUFACTURERS LIFE INSURANCE COMPANY, THE | 24,903 | $457K | 0.1% | 2026-Q1 |
| RENAISSANCE TECHNOLOGIES LLC trimmed | 24,262 | $446K | 0.1% | 2026-Q1 |
| CITIGROUP INC added | 20,169 | $371K | 0.1% | 2026-Q1 |
| Brevan Howard Capital Management LP new | 19,530 | $359K | 0.1% | 2026-Q1 |
| MORGAN STANLEY trimmed | 18,577 | $341K | 0.1% | 2026-Q1 |
| OMERS ADMINISTRATION Corp added | 17,800 | $327K | 0.1% | 2026-Q1 |
| NORTHERN TRUST CORP | 17,229 | $316K | 0.1% | 2026-Q1 |
| BNP PARIBAS FINANCIAL MARKETS added | 15,694 | $288K | 0.1% | 2026-Q1 |
| ALGERT GLOBAL LLC new | 13,806 | $254K | 0.0% | 2026-Q1 |
| Verdad Advisers, LP new | 12,748 | $234K | 0.0% | 2026-Q1 |
| Cannon Global Investment Management, LLC new | 10,200 | $187K | 0.0% | 2026-Q1 |
| Vanguard Global Advisers, LLC new | 3,469 | $64K | 0.0% | 2026-Q1 |
| Parallel Advisors, LLC new | 264 | $5K | 0.0% | 2026-Q1 |
| Allworth Financial LP new | 161 | $3K | 0.0% | 2026-Q1 |
| SBI Securities Co., Ltd. | 68 | $1K | 0.0% | 2026-Q1 |
| ROYAL BANK OF CANADA added | 51 | $1K | 0.0% | 2026-Q1 |
| Fortitude Family Office, LLC new | 40 | $735 | 0.0% | 2026-Q1 |
| OSAIC HOLDINGS, INC. | 26 | $477 | 0.0% | 2026-Q1 |
| Caitong International Asset Management Co., Ltd new | 4 | $73 | 0.0% | 2026-Q1 |
| Paradigm Biocapital Advisors LP new | 642,721 | $10M | 2.0% | 2025-Q2 stale |
| VANGUARD GROUP INC trimmed | 557,506 | $7M | 1.3% | 2025-Q4 stale |
| Boxer Capital Management, LLC | 453,686 | $5M | 1.0% | 2025-Q4 stale |
| Commodore Capital LP trimmed | 450,829 | $5M | 1.0% | 2025-Q3 stale |
| BRAIDWELL LP new | 261,504 | $4M | 0.8% | 2025-Q2 stale |
| Driehaus Capital Management LLC | 302,457 | $4M | 0.7% | 2025-Q4 stale |
| Frazier Life Sciences Management, L.P. trimmed | 272,951 | $3M | 0.6% | 2025-Q3 stale |
| HEIGHTS CAPITAL MANAGEMENT, INC new | 264,000 | $3M | 0.6% | 2025-Q4 stale |
| ADAGE CAPITAL PARTNERS GP, L.L.C. added | 200,005 | $2M | 0.5% | 2025-Q3 stale |
| Soleus Capital Management, L.P. trimmed | 200,000 | $2M | 0.5% | 2025-Q3 stale |
| WELLINGTON MANAGEMENT GROUP LLP added | 143,412 | $2M | 0.3% | 2025-Q4 stale |
| Blackstone Inc. | 75,614 | $897K | 0.2% | 2025-Q4 stale |
| Jefferies Financial Group Inc. trimmed | 64,244 | $762K | 0.1% | 2025-Q4 stale |
| TWO SIGMA ADVISERS, LP new | 32,500 | $385K | 0.1% | 2025-Q4 stale |
| CITADEL ADVISORS LLC new | 25,593 | $304K | 0.1% | 2025-Q3 stale |
| JANE STREET GROUP, LLC new | 22,965 | $272K | 0.1% | 2025-Q4 stale |
| Affinity Asset Advisors, LLC trimmed | 17,998 | $214K | 0.0% | 2025-Q3 stale |
| HRT FINANCIAL LP new | 13,083 | $155K | 0.0% | 2025-Q4 stale |
| Tower Research Capital LLC (TRC) added | 409 | $5K | 0.0% | 2025-Q4 stale |
| RAYMOND JAMES FINANCIAL INC new | 50 | $807 | 0.0% | 2025-Q2 stale |
| GROUP ONE TRADING LLC trimmed | 4 | $47 | 0.0% | 2025-Q4 stale |
| CONCOURSE FINANCIAL GROUP SECURITIES, INC. new | 0 | — | 0.0% | 2025-Q2 stale |
| Avion Wealth new | 40 | — | 0.0% | 2025-Q4 stale |
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.