Kiniksa Pharmaceuticals, Ltd.
Kiniksa Pharmaceuticals, Ltd. (KNSA) Stock Ownership
Institutional vs insider vs public ownership from 13F and float data — top holders, activity, and insider trades below.
SEC 13F · FMP · KNSA · as of Sep 30, 2025
Ownership Breakdown
211
Institutional Holders
▲ 18 vs Q2
$1.58B
Total Inst. Value
▲ $483.77M vs Q2
75.17M
Shares Outstanding
freeFloat 95.61%
40.80M
13F Shares Held
▲ 1.03M vs Q2
Institutional ownership = 13F shares ÷ total outstanding. Insider % = 100 − free float. Public % = free float − institution %. Data: FMP /symbol-positions-summary + /shares-float + SEC EDGAR.
Top Institutional Holders
KNSA largest shareholders · institutional ownership
Q3 2025 · SEC 13F
Showing top 10 holders
| Holder | Shares | % Owned | Weight | Value | Reported | Change |
|---|---|---|---|---|---|---|
RUBRIC CAPITAL MANAGEMENT LP pharmaceutical preparations | 4.00M | 5.45% | 5.45% | $155.32B | Nov 14, 2025 | ▲ 90.2K |
VANGUARD GROUP INC pharmaceutical preparations | 3.06M | 4.17% | 4.17% | $118.94B | Nov 7, 2025 | ▼ 68.5K |
BAKER BROS. ADVISORS LP pharmaceutical preparations | 2.82M | 3.85% | 3.85% | $109.68B | Nov 14, 2025 | — held |
TANG CAPITAL MANAGEMENT LLC pharmaceutical preparations | 2.33M | 3.17% | 3.17% | $90.42B | Nov 14, 2025 | — held |
FAIRMOUNT FUNDS MANAGEMENT LLC pharmaceutical preparations | 1.77M | 2.41% | 2.41% | $68.84B | Nov 14, 2025 | — held |
ACADIAN ASSET MANAGEMENT LLC pharmaceutical preparations | 1.62M | 2.20% | 2.20% | $62.82B | Nov 13, 2025 | ▲ 350.5K |
MORGAN STANLEY pharmaceutical preparations | 1.36M | 1.86% | 1.86% | $52.92B | May 27, 2026 | ▲ 296.6K |
D. E. SHAW & CO., INC. pharmaceutical preparations | 1.13M | 1.54% | 1.54% | $44.04B | Nov 14, 2025 | ▲ 342.9K |
ARROWSTREET CAPITAL, LIMITED PARTNERSHIP pharmaceutical preparations | 1.07M | 1.45% | 1.45% | $41.48B | Nov 13, 2025 | ▲ 332.8K |
MILLENNIUM MANAGEMENT LLC pharmaceutical preparations | 1.01M | 1.38% | 1.38% | $39.38B | Nov 14, 2025 | ▼ 5.8K |
Data from SEC Form 13F filings. Ownership bar normalised to largest holder. Change flags: isNew / isSoldOut / changeInSharesNumber (FMP extract-analytics/holder).
Institutional Activity
Q3 2025 vs prior quarter
Q3 2025
23
Increased
+4.29M shares4
New Positions
first time holders19
Decreased
−2.30M shares0
Sold Out
fully exitedNet shares change (top 50)
+1.99M
+4.29M / −2.30M
Net new holders
+8
4 new / 0 exited
Based on top 50 institutional holders by position size. Fields: isNew, isSoldOut, changeInSharesNumber (FMP extract-analytics/holder, limit=50).
Insider Buying vs Selling
KNSA insider trading · insider activity
Source: SEC Form 4
61
Buy transactions
66
Sell transactions
0.92
Buy/Sell ratio
$2M
Total disposed
Recent Insider Transactions
Showing 10 most recent · Common Stock only
| Name · Role | Date | Type | Shares | Price | Value | After Trans. | Filing |
|---|---|---|---|---|---|---|---|
Quart Barry D director | May 29, 2026 | Award | 12,158 | $48.38 | $588.2K | 12.2K | Form 4 ↗ |
Quart Barry D director | May 29, 2026 | Award | 2,026 | — | — | 2.0K | Form 4 ↗ |
Popovits Kimberly J director | May 29, 2026 | Award | 12,158 | $48.38 | $588.2K | 12.2K | Form 4 ↗ |
Popovits Kimberly J director | May 29, 2026 | Award | 2,026 | — | — | 2.0K | Form 4 ↗ |
Patel Sanj K CHAIRMAN & CEO | Jun 1, 2026 | C-Conversion | 900,000 | — | — | 951.8K | Form 4 ↗ |
Patel Sanj K CHAIRMAN & CEO | Jun 1, 2026 | C-Conversion | 900,000 | — | — | 626.2K | Form 4 ↗ |
McCain Tracey L director | May 29, 2026 | Award | 12,158 | $48.38 | $588.2K | 12.2K | Form 4 ↗ |
McCain Tracey L director | May 29, 2026 | Award | 2,026 | — | — | 2.0K | Form 4 ↗ |
Malley Thomas director | May 29, 2026 | Award | 12,158 | $48.38 | $588.2K | 12.2K | Form 4 ↗ |
Malley Thomas director | May 29, 2026 | Award | 2,026 | — | — | 2.0K | Form 4 ↗ |
Source: /insider-trading/search (FMP stable). Buy/Sell direction: acquisitionOrDisposition A=Buy, D=Sell. RSU vesting (M-Exempt) excluded from sentiment bar. All data from SEC EDGAR public filings.
About institutional & insider ownership
Kiniksa Pharmaceuticals, Ltd. (KNSA) is primarily owned by institutional investors, who hold approximately 54.3% of total shares outstanding. Company insiders own approximately 4.39%, while retail and public investors account for the remaining 41.33%.
The largest institutional shareholder of Kiniksa Pharmaceuticals, Ltd. is RUBRIC CAPITAL MANAGEMENT LP, holding approximately 4.00 million shares — equal to 5.45% of outstanding shares — as of September 30, 2025.
A total of 211 institutional investors currently hold KNSA stock, with a combined institutional value of approximately $1.58 billion as of the most recent 13F filing period.
Frequently asked questions
KNSA ownershipKiniksa Pharmaceuticals, Ltd. (KNSA) is primarily owned by institutional investors, who hold approximately 54.3% of shares. The largest shareholder is RUBRIC CAPITAL MANAGEMENT LP with a 5.45% stake. Company insiders hold 4.39%. Data sourced from SEC Form 13F as of September 30, 2025.