Inhibrx Biosciences (INBX) insider buying
14 open-market purchases of INBX by Inhibrx Biosciences's executives and directors since September 2026, worth $5M in total, from SEC Form 4 filings.
The most recent: Mark Lappe, Chief Executive Officer bought $148,320 on September 28, 2026.
The biggest buyer over the period is Mark Lappe (Chief Executive Officer): 10 purchases, $4M.
By year
| Year | Purchases | Value |
|---|---|---|
| 2026 | 14 | $5M |
Biggest buyers
| Insider | Buys | Value |
|---|---|---|
| Mark Lappe Chief Executive Officer | 10 | $4M |
| Jon Faiz Kayyem Director | 3 | $2M |
| Douglas Forsyth Director | 1 | $286,617 |
Every purchase
Newest first. From SEC Form 4 filings. Insider buying across the market.
| Date | Insider | Shares | Price | Value | Filing |
|---|---|---|---|---|---|
| Sep 28, 2026 | Mark Lappe Chief Executive Officer |
1,500 | $98.88 | $148,320 | Form 4 |
| Sep 28, 2026 | Mark Lappe Chief Executive Officer |
3,000 | $101.70 | $305,106 | Form 4 |
| Sep 25, 2026 | Mark Lappe Chief Executive Officer |
3,324 | $98.87 | $328,630 | Form 4 |
| Sep 25, 2026 | Mark Lappe Chief Executive Officer |
2,176 | $99.60 | $216,727 | Form 4 |
| Sep 23, 2026 | Jon Faiz Kayyem Director |
5,000 | $100.00 | $500,000 | Form 4 |
| Sep 16, 2026 | Jon Faiz Kayyem Director |
5,000 | $100.00 | $500,000 | Form 4 |
| Sep 8, 2026 | Mark Lappe Chief Executive Officer |
9,681 | $112.28 | $1M | Form 4 |
| Sep 8, 2026 | Douglas Forsyth Director |
2,500 | $114.65 | $286,617 | Form 4 |
| Sep 8, 2026 | Jon Faiz Kayyem Director |
5,000 | $113.52 | $567,580 | Form 4 |
| Sep 8, 2026 | Mark Lappe Chief Executive Officer |
5,895 | $99.29 | $585,343 | Form 4 |
| Sep 8, 2026 | Mark Lappe Chief Executive Officer |
6,605 | $100.64 | $664,719 | Form 4 |
| Sep 8, 2026 | Mark Lappe Chief Executive Officer |
1,100 | $107.12 | $117,836 | Form 4 |
| Sep 8, 2026 | Mark Lappe Chief Executive Officer |
500 | $108.23 | $54,118 | Form 4 |
| Sep 8, 2026 | Mark Lappe Chief Executive Officer |
1,219 | $111.88 | $136,382 | Form 4 |
Questions
Are Inhibrx Biosciences insiders buying the stock?
14 open-market purchases of INBX by Inhibrx Biosciences's executives and directors since September 2026, worth $5M in total, from SEC Form 4 filings. The most recent: Mark Lappe, Chief Executive Officer bought $148,320 on September 28, 2026.
What counts as insider buying here?
Open-market purchases (Form 4 code P) by officers and directors. Option exercises, grants and purchases by 10% owners are left out.
From Inhibrx Biosciences's annual reports filed with the SEC (XBRL data), standardised by Investingly. Information only, not investment advice.