Inhibrx Biosciences, Inc.
Ownership
Ownership Structure
Who owns Inhibrx Biosciences, Inc. (INBX)? This page shows the largest institutions and funds, the ownership structure and the latest insider transactions. 58.3% of the shares are freely tradable; institutional investors hold 83.1%.
Largest Shareholders
Institutions
| Name | Stake (%) | Shares | Change (%) | Date |
|---|---|---|---|---|
| Morgan Stanley - Brokerage Accounts | 8.89 | 1,308,051 | +3.6 | 06/30/2026 |
| Perceptive Advisors LLC | 8.82 | 1,297,763 | -10.0 | 06/30/2026 |
| Sanofi | 7.87 | 1,157,926 | +0.0 | 06/30/2026 |
| Viking Global Investors LP | 7.64 | 1,123,929 | -21.8 | 06/30/2026 |
| HighTower Advisors, LLC | 5.92 | 870,551 | +0.0 | 06/30/2026 |
| Bank of America Corp | 5.72 | 841,141 | +2,473.6 | 06/30/2026 |
| BlackRock Inc | 5.61 | 825,972 | +3.4 | 06/30/2026 |
| Schonfeld Strategic Advisors LLC | 4.74 | 697,586 | +173.7 | 06/30/2026 |
| State Street Corp | 4.35 | 640,458 | +16.3 | 06/30/2026 |
| Vanguard Capital Management, LLC | 3.35 | 492,477 | +1.2 | 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 |
|---|---|---|---|---|---|
| Lappe Mark | Chief Executive Officer | 915,388 | 65,724,858 $ | Oct 14, 2026 | indirect |
| Kayyem Jon Faiz | Director | 434,360 | 31,187,048 $ | Sep 23, 2026 | indirect |
| Forsyth Douglas | Director | 227,064 | 16,303,195 $ | Sep 8, 2026 | indirect |
| Manhard Kimberly | Director | 7,500 | 538,500 $ | Sep 15, 2026 | indirect |
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 14, 2026 | Lappe Mark | Chief Executive Officer | Buy | 2,451 | 85.00 | 208,333 |
| Oct 14, 2026 | Lappe Mark | Chief Executive Officer | Buy | 2,449 | 84.07 | 205,889 |
| Oct 14, 2026 | Lappe Mark | Chief Executive Officer | Buy | 100 | 85.76 | 8,576 |
| Oct 14, 2026 | Lappe Mark | Chief Executive Officer | Buy | 2,470 | 85.00 | 209,948 |
| Sep 28, 2026 | Lappe Mark | Chief Executive Officer | Buy | 3,000 | 101.70 | 305,106 |
| Sep 28, 2026 | Lappe Mark | Chief Executive Officer | Buy | 1,500 | 98.88 | 148,320 |
| Sep 25, 2026 | Lappe Mark | Chief Executive Officer | Buy | 2,176 | 99.60 | 216,727 |
| Sep 25, 2026 | Lappe Mark | Chief Executive Officer | Buy | 3,324 | 98.87 | 328,630 |
| Sep 23, 2026 | Kayyem Jon Faiz | Director | Buy | 5,000 | 100.00 | 500,000 |
| Sep 16, 2026 | Kayyem Jon Faiz | Director | Buy | 5,000 | 100.00 | 500,000 |
| Sep 15, 2026 | Manhard Kimberly | Director | Sell | 500 | 105.05 | 52,525 |
| Sep 14, 2026 | Manhard Kimberly | Director | Sell | 500 | 110.26 | 55,130 |
| Sep 11, 2026 | Manhard Kimberly | Director | Sell | 500 | 111.78 | 55,888 |
| Sep 9, 2026 | Manhard Kimberly | Director | Sell | 500 | 115.80 | 57,898 |
| Sep 8, 2026 | Manhard Kimberly | Director | Sell | 500 | 115.14 | 57,570 |
| Sep 8, 2026 | Kayyem Jon Faiz | Director | Buy | 5,000 | 113.52 | 567,580 |
| Sep 8, 2026 | Lappe Mark | Chief Executive Officer | Buy | 9,681 | 112.28 | 1,087,001 |
| Sep 8, 2026 | Lappe Mark | Chief Executive Officer | Buy | 1,219 | 111.88 | 136,382 |
| Sep 8, 2026 | Lappe Mark | Chief Executive Officer | Buy | 500 | 108.24 | 54,118 |
| Sep 8, 2026 | Lappe Mark | Chief Executive Officer | Buy | 1,100 | 107.12 | 117,836 |
| Sep 8, 2026 | Lappe Mark | Chief Executive Officer | Buy | 6,605 | 100.64 | 664,719 |
| Sep 8, 2026 | Lappe Mark | Chief Executive Officer | Buy | 5,895 | 99.29 | 585,343 |
| Sep 8, 2026 | Forsyth Douglas | Director | Buy | 2,500 | 114.65 | 286,617 |
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.