Karyopharm Therapeutics Inc
Ownership
Ownership Structure
Who owns Karyopharm Therapeutics Inc (KPTI)? This page shows the largest institutions and funds, the ownership structure and the latest insider transactions. 76.3% of the shares are freely tradable; institutional investors hold 83.7%.
Largest Shareholders
Institutions
| Name | Stake (%) | Shares | Change (%) | Date |
|---|---|---|---|---|
| RA Capital Management, LLC | 8.45 | 1,917,354 | +0.0 | 06/30/2026 |
| Adage Capital Partners Gp LLC | 6.71 | 1,521,322 | -15.8 | 06/30/2026 |
| The Goldman Sachs Group Inc | 6.28 | 1,424,658 | +50.3 | 06/30/2026 |
| BlackRock Inc | 6.26 | 1,418,799 | +479.3 | 06/30/2026 |
| Kalehua Capital Management LLC | 6.05 | 1,371,288 | +0.0 | 06/30/2026 |
| Vanguard Capital Management, LLC | 4.23 | 958,979 | +29.6 | 06/30/2026 |
| Catalio Capital Management, LP | 4.15 | 940,855 | +4.8 | 06/30/2026 |
| Avidity Partners Management LP | 4.08 | 924,487 | -0.3 | 06/30/2026 |
| T. Rowe Price Investment Management,Inc. | 3.47 | 786,309 | -49.0 | 06/30/2026 |
| Two Sigma Investments LLC | 3.07 | 695,264 | +359.7 | 06/30/2026 |
Largest reported positions according to regulatory filings; stake as a percentage of shares outstanding, change versus the previous filing. Source: fundamentals data.
Insider holdings
| Person | Role | Shares | Value | As of | Type |
|---|---|---|---|---|---|
| Poulton Stuart | EVP, Chief Development Officer | 94,632 | 62,646 $ | Jul 28, 2026 | direct |
| Abate Kristin | Chief Accounting Officer | 18,616 | 12,324 $ | Oct 16, 2026 | direct |
Holdings as of each person's most recent SEC Form 4 filing — excluding options and RSUs, which are not shares yet. Holdings may have changed between two filings.
Insiders
Insider Transactions
| Date | Person | Role | Type | Shares | Price | Value |
|---|---|---|---|---|---|---|
| Oct 16, 2026 | Abate Kristin | Chief Accounting Officer | Sell | 4,788 | 0.344 | 1,647 |
| Oct 1, 2026 | Abate Kristin | Chief Accounting Officer | Sell | 378 | 1.19 | 450 |
| Sep 1, 2026 | Abate Kristin | Chief Accounting Officer | Sell | 19 | 2.02 | 38 |
| Jul 28, 2026 | Poulton Stuart | EVP, Chief Development Officer | Sell | 189 | 7.10 | 1,342 |
| Apr 21, 2026 | Reshma Rangwala | EVP | Sell | 449 | 8.94 | 4,014 |
Reportable transactions by officers and major shareholders from SEC Form 4 filings. "Other" includes things like stock grants and option exercises without a buy/sell character. View all insider transactions →
Data as of: October 30, 2026 · Source: fundamental data & SEC filings (annual and quarterly reports, 10-K/10-Q)
Note: pure fact-based analysis, not investment advice and not a solicitation to buy or sell. All figures without guarantee.