Who owns Cytokinetics (CYTK)
Which tracked institutional funds hold CYTK, how they are positioned, and who is buying versus exiting — from SEC Form 13F-HR filings. See CYTK company fundamentals →
Ownership as of the 2026-Q1 13F filings (latest filed 2026-05-18). 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
135 tracked funds added or opened CYTK while 95 trimmed or exited it between 2025-Q4 and 2026-Q1 — the tape is split. When large holders disagree on a name, the funds moving first are sometimes ahead of the story.
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
CYTK’s largest tracked holder by dollar value, BlackRock, Inc., sizes it at 0.0% of its own reported 13F book, while the median holder sizes it at 0.1% of theirs — a 0.0pp gap the other way — the median holder sizes CYTK more heavily than its largest holder by dollar value does.
Book-share is each fund’s reported value in CYTK 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 442 tracked filers holding CYTK, 257 increased or opened the position and 203 reduced or closed it; over the same quarter, open-market insider Form 4 buying and selling roughly offset.
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 CYTK 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 43
- VANGUARD PORTFOLIO MANAGEMENT LLC$385M
- VANGUARD CAPITAL MANAGEMENT LLC$362M
- Avoro Capital Advisors LLC$220M
- Paradigm Biocapital Advisors LP$98M
- WILLIAM BLAIR INVESTMENT MANAGEMENT, LLC$72M
- BALYASNY ASSET MANAGEMENT L.P.$65M
Full exits 25
- VANGUARD GROUP INC$766M
- Rosalind Advisors, Inc.$12M
- TWO SIGMA ADVISERS, LP$11M
- RENAISSANCE TECHNOLOGIES LLC$11M
- Hood River Capital Management LLC$9M
- READYSTATE ASSET MANAGEMENT LP$8M
Largest adds
- T. Rowe Price Investment Management, Inc.$558M
- UBS Group AG$65M
- Point72 Asset Management, L.P.$41M
- D. E. Shaw & Co., Inc.$39M
- Logos Global Management LP$39M
- WELLINGTON MANAGEMENT GROUP LLP$22M
Largest trims
- NORTHWESTERN MUTUAL WEALTH MANAGEMENT CO$386M
- Pacer Advisors, Inc.$312M
- Deep Track Capital, LP$121M
- FMR LLC$108M
- BlackRock, Inc.$100M
- Polar Capital Holdings Plc$44M
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 |
|---|---|---|---|---|
| BlackRock, Inc. added | 20,094,362 | $1.7B | 15.5% | 2026-Q2 |
| T. Rowe Price Investment Management, Inc. added | 17,523,840 | $1.2B | 10.5% | 2026-Q1 |
| WELLINGTON MANAGEMENT GROUP LLP trimmed | 6,931,770 | $591M | 5.4% | 2026-Q2 |
| STATE STREET CORP added | 6,494,233 | $553M | 5.0% | 2026-Q2 |
| FMR LLC trimmed | 5,031,782 | $429M | 3.9% | 2026-Q2 |
| VANGUARD PORTFOLIO MANAGEMENT LLC new | 5,843,782 | $385M | 3.5% | 2026-Q1 |
| VANGUARD CAPITAL MANAGEMENT LLC new | 5,488,634 | $362M | 3.3% | 2026-Q1 |
| Avoro Capital Advisors LLC new | 3,333,333 | $220M | 2.0% | 2026-Q1 |
| GEODE CAPITAL MANAGEMENT, LLC added | 3,215,415 | $212M | 1.9% | 2026-Q1 |
| BANK OF AMERICA CORP /DE/ added | 3,125,436 | $206M | 1.9% | 2026-Q1 |
| RTW INVESTMENTS, LP | 2,721,158 | $179M | 1.6% | 2026-Q1 |
| PRICE T ROWE ASSOCIATES INC /MD/ added | 1,958,946 | $167M | 1.5% | 2026-Q2 |
| GOLDMAN SACHS GROUP INC trimmed | 2,205,758 | $145M | 1.3% | 2026-Q1 |
| Capital Research Global Investors added | 1,686,625 | $144M | 1.3% | 2026-Q2 |
| UBS Group AG added | 2,077,277 | $137M | 1.2% | 2026-Q1 |
| Point72 Asset Management, L.P. added | 1,587,712 | $135M | 1.2% | 2026-Q2 |
| Capital International Investors trimmed | 1,305,848 | $111M | 1.0% | 2026-Q2 |
| Polar Capital Holdings Plc trimmed | 1,661,248 | $109M | 1.0% | 2026-Q1 |
| Integral Health Asset Management, LLC added | 1,600,000 | $105M | 1.0% | 2026-Q1 |
| Invesco Ltd. added | 1,235,323 | $105M | 1.0% | 2026-Q2 |
| MORGAN STANLEY added | 1,505,075 | $99M | 0.9% | 2026-Q1 |
| Paradigm Biocapital Advisors LP added | 1,480,857 | $98M | 0.9% | 2026-Q1 |
| NORTHERN TRUST CORP added | 1,441,634 | $95M | 0.9% | 2026-Q1 |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC added | 1,397,045 | $92M | 0.8% | 2026-Q1 |
| Deep Track Capital, LP trimmed | 1,374,320 | $91M | 0.8% | 2026-Q1 |
| D. E. Shaw & Co., Inc. added | 1,048,103 | $89M | 0.8% | 2026-Q2 |
| NORGES BANK trimmed | 1,015,522 | $87M | 0.8% | 2026-Q2 |
| Frazier Life Sciences Management, L.P. added | 1,159,879 | $76M | 0.7% | 2026-Q1 |
| PRINCIPAL FINANCIAL GROUP INC added | 1,093,485 | $72M | 0.7% | 2026-Q1 |
| WILLIAM BLAIR INVESTMENT MANAGEMENT, LLC new | 1,087,591 | $72M | 0.6% | 2026-Q1 |
| Bank of New York Mellon Corp added | 1,006,185 | $66M | 0.6% | 2026-Q1 |
| Woodline Partners LP trimmed | 1,000,428 | $66M | 0.6% | 2026-Q1 |
| Royalty Pharma Sub-Manager, LLC | 980,392 | $65M | 0.6% | 2026-Q1 |
| BALYASNY ASSET MANAGEMENT L.P. trimmed | 711,676 | $61M | 0.5% | 2026-Q2 |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP added | 898,951 | $59M | 0.5% | 2026-Q1 |
| Logos Global Management LP added | 875,000 | $58M | 0.5% | 2026-Q1 |
| JPMORGAN CHASE & CO trimmed | 903,805 | $57M | 0.5% | 2026-Q1 |
| BNP PARIBAS FINANCIAL MARKETS added | 854,374 | $56M | 0.5% | 2026-Q1 |
| Melqart Asset Management (UK) Ltd added | 843,949 | $56M | 0.5% | 2026-Q1 |
| CITADEL ADVISORS LLC trimmed | 640,945 | $55M | 0.5% | 2026-Q2 |
| VANGUARD FIDUCIARY TRUST CO new | 799,622 | $53M | 0.5% | 2026-Q1 |
| Qube Research & Technologies Ltd added | 779,446 | $51M | 0.5% | 2026-Q1 |
| Fisher Asset Management, LLC trimmed | 768,264 | $51M | 0.5% | 2026-Q1 |
| ARMISTICE CAPITAL, LLC trimmed | 764,538 | $50M | 0.5% | 2026-Q1 |
| Pictet Asset Management Holding SA trimmed | 750,953 | $49M | 0.4% | 2026-Q1 |
| BNP PARIBAS ASSET MANAGEMENT Holding S.A. trimmed | 714,344 | $47M | 0.4% | 2026-Q1 |
| Affinity Asset Advisors, LLC trimmed | 700,483 | $46M | 0.4% | 2026-Q1 |
| FEDERATED HERMES, INC. added | 699,453 | $46M | 0.4% | 2026-Q1 |
| Nationale-Nederlanden Powszechne Towarzystwo Emerytalne S.A. trimmed | 660,310 | $44M | 0.4% | 2026-Q1 |
| ADAR1 Capital Management, LLC added | 632,556 | $42M | 0.4% | 2026-Q1 |
| BROWN ADVISORY INC trimmed | 614,655 | $41M | 0.4% | 2026-Q1 |
| Siren, L.L.C. added | 613,952 | $40M | 0.4% | 2026-Q1 |
| MARSHALL WACE, LLP trimmed | 451,467 | $38M | 0.3% | 2026-Q2 |
| Foresite Capital Management IV, LLC added | 503,295 | $33M | 0.3% | 2026-Q1 |
| MPM BIOIMPACT LLC new | 500,000 | $33M | 0.3% | 2026-Q1 |
| GW&K Investment Management, LLC added | 494,619 | $33M | 0.3% | 2026-Q1 |
| Aberdeen Group plc added | 483,274 | $32M | 0.3% | 2026-Q1 |
| EVENTIDE ASSET MANAGEMENT, LLC trimmed | 479,098 | $32M | 0.3% | 2026-Q1 |
| AMERICAN CENTURY COMPANIES INC added | 443,957 | $29M | 0.3% | 2026-Q1 |
| ALLIANCEBERNSTEIN L.P. added | 459,087 | $29M | 0.3% | 2026-Q1 |
| TD Asset Management Inc trimmed | 420,846 | $28M | 0.3% | 2026-Q1 |
| TWO SIGMA INVESTMENTS, LP added | 317,411 | $27M | 0.2% | 2026-Q2 |
| FRANKLIN RESOURCES INC trimmed | 409,784 | $27M | 0.2% | 2026-Q1 |
| RHUMBLINE ADVISERS added | 369,575 | $24M | 0.2% | 2026-Q1 |
| GROUP ONE TRADING LLC trimmed | 363,997 | $24M | 0.2% | 2026-Q1 |
| Nuveen, LLC trimmed | 351,809 | $23M | 0.2% | 2026-Q1 |
| GSK plc | 340,434 | $22M | 0.2% | 2026-Q1 |
| Candriam S.C.A. added | 335,208 | $22M | 0.2% | 2026-Q1 |
| GILDER GAGNON HOWE & CO LLC trimmed | 330,989 | $22M | 0.2% | 2026-Q1 |
| ExodusPoint Capital Management, LP added | 249,259 | $21M | 0.2% | 2026-Q2 |
| Capital World Investors added | 248,815 | $21M | 0.2% | 2026-Q2 |
| MASSACHUSETTS FINANCIAL SERVICES CO /MA/ trimmed | 311,649 | $21M | 0.2% | 2026-Q1 |
| AMERIPRISE FINANCIAL INC trimmed | 302,802 | $20M | 0.2% | 2026-Q1 |
| E. Ohman J:or Asset Management AB trimmed | 300,762 | $20M | 0.2% | 2026-Q1 |
| Vestal Point Capital, LP trimmed | 300,000 | $20M | 0.2% | 2026-Q1 |
| Trails Edge Capital Partners, LP new | 300,000 | $20M | 0.2% | 2026-Q1 |
| First Turn Management, LLC trimmed | 283,700 | $19M | 0.2% | 2026-Q1 |
| Ikarian Capital, LLC added | 283,572 | $19M | 0.2% | 2026-Q1 |
| JANUS HENDERSON GROUP PLC added | 282,121 | $19M | 0.2% | 2026-Q1 |
| Susquehanna Portfolio Strategies, LLC | 278,429 | $18M | 0.2% | 2026-Q1 |
| VOYA INVESTMENT MANAGEMENT LLC added | 259,459 | $17M | 0.2% | 2026-Q1 |
| CITIGROUP INC added | 249,243 | $16M | 0.1% | 2026-Q1 |
| Handelsbanken Fonder AB added | 247,300 | $16M | 0.1% | 2026-Q1 |
| Caption Management, LLC added | 245,000 | $16M | 0.1% | 2026-Q1 |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC added | 240,632 | $16M | 0.1% | 2026-Q1 |
| Swiss National Bank added | 229,800 | $15M | 0.1% | 2026-Q1 |
| Sarissa Capital Management LP trimmed | 228,623 | $15M | 0.1% | 2026-Q1 |
| HSBC HOLDINGS PLC added | 221,999 | $15M | 0.1% | 2026-Q1 |
| DAFNA Capital Management LLC trimmed | 217,497 | $14M | 0.1% | 2026-Q1 |
| Freestone Grove Partners LP new | 216,769 | $14M | 0.1% | 2026-Q1 |
| Catalio Capital Management, LP trimmed | 215,501 | $14M | 0.1% | 2026-Q1 |
| AQR CAPITAL MANAGEMENT LLC added | 161,903 | $14M | 0.1% | 2026-Q2 |
| Mirador Capital Partners LP added | 202,673 | $13M | 0.1% | 2026-Q1 |
| EMERALD ADVISERS, LLC new | 198,811 | $13M | 0.1% | 2026-Q1 |
| VANGUARD GROUP INC added | 12,048,131 | $766M | 6.9% | 2025-Q4 stale |
| WESTFIELD CAPITAL MANAGEMENT CO LP added | 1,310,336 | $53M | 0.5% | 2025-Q1 stale |
| RP Management, LLC | 980,392 | $39M | 0.4% | 2025-Q1 stale |
| ORBIMED ADVISORS LLC trimmed | 1,077,000 | $36M | 0.3% | 2025-Q2 stale |
| JENNISON ASSOCIATES LLC new | 673,932 | $27M | 0.2% | 2025-Q1 stale |
| Pentwater Capital Management LP | 300,000 | $16M | 0.1% | 2025-Q3 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.