Who owns Kiniksa Pharmaceuticals (KNSA)
Which tracked institutional funds hold KNSA, how they are positioned, and who is buying versus exiting — from SEC Form 13F-HR filings. See KNSA 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
103 tracked funds added or opened KNSA while 51 trimmed or exited it between 2026-Q1 and 2026-Q2 — 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
KNSA’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 KNSA 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 255 tracked filers holding KNSA, 151 increased or opened the position and 119 reduced or closed it; over the same quarter, open-market insider Form 4s were net sales.
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 KNSA 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 23
- Jupiter Topco LLC$37M
- STEMPOINT CAPITAL LP$13M
- SEGALL BRYANT & HAMILL, LLC$5M
- RENAISSANCE TECHNOLOGIES LLC$4M
- TRUIST FINANCIAL CORP$3M
- MUTUAL OF AMERICA CAPITAL MANAGEMENT LLC$3M
Full exits 22
- ACADIAN ASSET MANAGEMENT LLC$64M
- SG Americas Securities, LLC$31M
- JANUS HENDERSON GROUP PLC$23M
- MARSHALL WACE, LLP$15M
- Parkman Healthcare Partners LLC$12M
- VOLORIDGE INVESTMENT MANAGEMENT, LLC$6M
Largest adds
- BlackRock, Inc.$152M
- FMR LLC$121M
- Rubric Capital Management LP$75M
- Invesco Ltd.$48M
- BAKER BROS. ADVISORS LP$45M
- STATE STREET CORP$41M
Largest trims
- MILLENNIUM MANAGEMENT LLC$21M
- CITADEL ADVISORS LLC$20M
- SUSQUEHANNA INTERNATIONAL GROUP, LLP$17M
- Qube Research & Technologies Ltd$14M
- D. E. Shaw & Co., Inc.$10M
- Soleus Capital Management, L.P.$9M
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 | 6,971,361 | $446M | 15.7% | 2026-Q2 |
| Rubric Capital Management LP added | 3,999,800 | $256M | 9.0% | 2026-Q2 |
| BAKER BROS. ADVISORS LP added | 2,834,643 | $181M | 6.4% | 2026-Q2 |
| BlackRock, Inc. added | 2,739,615 | $175M | 6.2% | 2026-Q2 |
| TANG CAPITAL MANAGEMENT LLC | 2,259,889 | $145M | 5.1% | 2026-Q2 |
| VANGUARD PORTFOLIO MANAGEMENT LLC added | 1,911,335 | $122M | 4.3% | 2026-Q2 |
| VANGUARD CAPITAL MANAGEMENT LLC added | 1,360,840 | $87M | 3.1% | 2026-Q2 |
| MORGAN STANLEY added | 1,011,143 | $65M | 2.3% | 2026-Q2 |
| ARROWSTREET CAPITAL, LIMITED PARTNERSHIP added | 957,514 | $61M | 2.2% | 2026-Q2 |
| Spruce Street Capital LP added | 918,070 | $59M | 2.1% | 2026-Q2 |
| DIMENSIONAL FUND ADVISORS LP added | 874,786 | $56M | 2.0% | 2026-Q2 |
| Invesco Ltd. added | 772,806 | $49M | 1.7% | 2026-Q2 |
| Driehaus Capital Management LLC added | 718,199 | $46M | 1.6% | 2026-Q2 |
| STATE STREET CORP added | 704,194 | $45M | 1.6% | 2026-Q2 |
| Point72 Asset Management, L.P. added | 659,493 | $42M | 1.5% | 2026-Q2 |
| RICE HALL JAMES & ASSOCIATES, LLC added | 624,928 | $40M | 1.4% | 2026-Q2 |
| Pictet Asset Management Holding SA trimmed | 608,650 | $39M | 1.4% | 2026-Q2 |
| GEODE CAPITAL MANAGEMENT, LLC added | 604,180 | $39M | 1.4% | 2026-Q2 |
| Jupiter Topco LLC new | 586,177 | $37M | 1.3% | 2026-Q2 |
| Connor, Clark & Lunn Investment Management Ltd. trimmed | 572,598 | $37M | 1.3% | 2026-Q2 |
| D. E. Shaw & Co., Inc. trimmed | 569,756 | $36M | 1.3% | 2026-Q2 |
| TWO SIGMA INVESTMENTS, LP added | 561,480 | $36M | 1.3% | 2026-Q2 |
| ALLIANCEBERNSTEIN L.P. trimmed | 556,151 | $27M | 0.9% | 2026-Q2 |
| VICTORY CAPITAL MANAGEMENT INC trimmed | 504,853 | $32M | 1.1% | 2026-Q2 |
| BNP PARIBAS FINANCIAL MARKETS trimmed | 437,192 | $28M | 1.0% | 2026-Q2 |
| MASSACHUSETTS FINANCIAL SERVICES CO /MA/ trimmed | 431,324 | $28M | 1.0% | 2026-Q2 |
| ORBIMED ADVISORS LLC added | 420,600 | $27M | 0.9% | 2026-Q2 |
| BANK OF AMERICA CORP /DE/ trimmed | 413,411 | $26M | 0.9% | 2026-Q2 |
| OBERWEIS ASSET MANAGEMENT INC/ added | 413,034 | $26M | 0.9% | 2026-Q2 |
| Aberdeen Group plc added | 403,485 | $26M | 0.9% | 2026-Q2 |
| Fisher Asset Management, LLC trimmed | 398,266 | $25M | 0.9% | 2026-Q2 |
| DEUTSCHE BANK AG\ trimmed | 387,606 | $25M | 0.9% | 2026-Q2 |
| AQR CAPITAL MANAGEMENT LLC added | 375,039 | $24M | 0.8% | 2026-Q2 |
| Penn Capital Management Company, LLC added | 368,114 | $24M | 0.8% | 2026-Q2 |
| NORTHERN TRUST CORP added | 315,246 | $20M | 0.7% | 2026-Q2 |
| BALYASNY ASSET MANAGEMENT L.P. trimmed | 309,682 | $20M | 0.7% | 2026-Q2 |
| Qube Research & Technologies Ltd trimmed | 304,080 | $19M | 0.7% | 2026-Q2 |
| NEW YORK STATE COMMON RETIREMENT FUND added | 272,579 | $17M | 0.6% | 2026-Q2 |
| NOMURA HOLDINGS INC trimmed | 270,724 | $17M | 0.6% | 2026-Q2 |
| Soleus Capital Management, L.P. trimmed | 246,353 | $16M | 0.6% | 2026-Q2 |
| ESSEX INVESTMENT MANAGEMENT CO LLC trimmed | 241,382 | $15M | 0.5% | 2026-Q2 |
| Bank of New York Mellon Corp added | 232,531 | $15M | 0.5% | 2026-Q2 |
| ArrowMark Colorado Holdings LLC trimmed | 215,546 | $14M | 0.5% | 2026-Q2 |
| STEMPOINT CAPITAL LP new | 209,234 | $13M | 0.5% | 2026-Q2 |
| GOLDMAN SACHS GROUP INC added | 191,364 | $12M | 0.4% | 2026-Q2 |
| SEI INVESTMENTS CO trimmed | 188,565 | $12M | 0.4% | 2026-Q2 |
| BRAIDWELL LP trimmed | 183,822 | $12M | 0.4% | 2026-Q2 |
| CASTLEARK MANAGEMENT LLC trimmed | 174,032 | $11M | 0.4% | 2026-Q2 |
| Rockefeller Capital Management L.P. | 173,438 | $11M | 0.4% | 2026-Q2 |
| PEREGRINE CAPITAL MANAGEMENT LLC trimmed | 161,464 | $10M | 0.4% | 2026-Q2 |
| Granahan Investment Management, LLC trimmed | 151,725 | $10M | 0.3% | 2026-Q2 |
| Squarepoint Ops LLC trimmed | 140,059 | $9M | 0.3% | 2026-Q2 |
| Nuveen, LLC added | 127,255 | $8M | 0.3% | 2026-Q2 |
| SILVERCREST ASSET MANAGEMENT GROUP LLC trimmed | 109,359 | $7M | 0.2% | 2026-Q2 |
| NORDEA INVESTMENT MANAGEMENT AB added | 107,157 | $7M | 0.2% | 2026-Q2 |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC added | 101,575 | $6M | 0.2% | 2026-Q2 |
| Universal- Beteiligungs- und Servicegesellschaft mbH trimmed | 99,852 | $6M | 0.2% | 2026-Q2 |
| GLOBEFLEX CAPITAL L P | 93,396 | $6M | 0.2% | 2026-Q2 |
| MILLENNIUM MANAGEMENT LLC trimmed | 93,364 | $6M | 0.2% | 2026-Q2 |
| Lisanti Capital Growth, LLC added | 87,305 | $6M | 0.2% | 2026-Q2 |
| Legato Capital Management LLC added | 87,297 | $6M | 0.2% | 2026-Q2 |
| Swiss National Bank added | 73,700 | $5M | 0.2% | 2026-Q2 |
| VANGUARD FIDUCIARY TRUST CO added | 72,351 | $5M | 0.2% | 2026-Q2 |
| SEGALL BRYANT & HAMILL, LLC added | 71,901 | $5M | 0.2% | 2026-Q2 |
| RENAISSANCE TECHNOLOGIES LLC new | 68,077 | $4M | 0.2% | 2026-Q2 |
| MANUFACTURERS LIFE INSURANCE COMPANY, THE added | 67,715 | $4M | 0.2% | 2026-Q2 |
| LAZARD ASSET MANAGEMENT LLC added | 67,291 | $4M | 0.2% | 2026-Q2 |
| Allspring Global Investments Holdings, LLC added | 65,097 | $4M | 0.1% | 2026-Q2 |
| RHUMBLINE ADVISERS added | 58,529 | $4M | 0.1% | 2026-Q2 |
| AMERICAN CENTURY COMPANIES INC added | 56,408 | $4M | 0.1% | 2026-Q2 |
| Informed Momentum Co LLC trimmed | 55,765 | $4M | 0.1% | 2026-Q2 |
| Linden Thomas Advisory Services, LLC trimmed | 54,803 | $4M | 0.1% | 2026-Q2 |
| Trexquant Investment LP trimmed | 53,507 | $3M | 0.1% | 2026-Q2 |
| HEALTHCARE OF ONTARIO PENSION PLAN TRUST FUND trimmed | 52,700 | $3M | 0.1% | 2026-Q2 |
| TRUIST FINANCIAL CORP new | 51,671 | $3M | 0.1% | 2026-Q2 |
| LOS ANGELES CAPITAL MANAGEMENT LLC added | 50,786 | $3M | 0.1% | 2026-Q2 |
| WELLS FARGO & COMPANY/MN added | 48,677 | $3M | 0.1% | 2026-Q2 |
| UBS Group AG trimmed | 45,174 | $3M | 0.1% | 2026-Q2 |
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM added | 42,559 | $3M | 0.1% | 2026-Q2 |
| CITADEL ADVISORS LLC trimmed | 41,665 | $3M | 0.1% | 2026-Q2 |
| Aquatic Capital Management LLC added | 41,528 | $3M | 0.1% | 2026-Q2 |
| MUTUAL OF AMERICA CAPITAL MANAGEMENT LLC new | 41,504 | $3M | 0.1% | 2026-Q2 |
| PDT Partners, LLC trimmed | 40,567 | $3M | 0.1% | 2026-Q2 |
| Man Group plc trimmed | 40,524 | $3M | 0.1% | 2026-Q2 |
| CITIGROUP INC added | 40,513 | $3M | 0.1% | 2026-Q2 |
| Cerity Partners LLC trimmed | 40,488 | $3M | 0.1% | 2026-Q2 |
| RAYMOND JAMES FINANCIAL INC added | 38,148 | $2M | 0.1% | 2026-Q2 |
| Legal & General Group Plc added | 35,549 | $2M | 0.1% | 2026-Q2 |
| PRICE T ROWE ASSOCIATES INC /MD/ added | 34,830 | $2M | 0.1% | 2026-Q2 |
| Timothy G. Youngquist 2020 Irrevocable Trust new | 34,341 | $2M | 0.1% | 2026-Q2 |
| ExodusPoint Capital Management, LP trimmed | 33,017 | $2M | 0.1% | 2026-Q2 |
| Voleon Capital Management LP trimmed | 32,806 | $2M | 0.1% | 2026-Q2 |
| AMERIPRISE FINANCIAL INC added | 32,571 | $2M | 0.1% | 2026-Q2 |
| LPL Financial LLC added | 32,420 | $2M | 0.1% | 2026-Q2 |
| JPMORGAN CHASE & CO trimmed | 31,553 | $2M | 0.1% | 2026-Q2 |
| Financial Enhancement Group LLC new | 31,391 | $2M | 0.1% | 2026-Q2 |
| Baird Financial Group, Inc. trimmed | 30,708 | $2M | 0.1% | 2026-Q2 |
| STATE OF WISCONSIN INVESTMENT BOARD added | 29,876 | $2M | 0.1% | 2026-Q2 |
| IEQ CAPITAL, LLC trimmed | 29,746 | $2M | 0.1% | 2026-Q2 |
| Artia Global Partners LP | 29,200 | $2M | 0.1% | 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.