INBX insider buying and SEC filings, explained
Inhibrx Biosciences, Inc. · CIK 2007919
Tracked: Forms 3/4/5, 8-K, NT · All filings on sec.gov
Insider activity in the last 12 months
Bought
$6.3M
Insiders who bought
3
Sold (not marked 10b5-1)
$279K
Planned sales (10b5-1)
$0
Insider purchases and sales, last 12 months
| Traded | Type | What was filed | Source |
|---|---|---|---|
| Oct 14, 2026 | Purchase (code P) | Mark Lappe (CEO and Director) bought 10,040 shares indirectly (by trust) at about $84.56 ($849K), reported as a purchase (code P). Holdings by trust up 1% to 745,588 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Oct 14, 2026, 6:58 PM ET |
| Sep 25–28, 2026 | Purchase (code P) | Mark Lappe (CEO and Director) bought 10,000 shares indirectly (by trust) between Sep 25 and Sep 28 at about $99.88 ($999K), reported as a purchase (code P). Holdings by trust up 1% to 740,548 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Sep 28, 2026 |
| Sep 23, 2026 | Purchase (code P) | Jon Faiz Kayyem (Director) bought 5,000 shares indirectly (by trust) at $100.00 ($500K), reported as a purchase (code P). Holdings by trust up 1% to 434,360 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Sep 23, 2026 |
| Sep 16, 2026 | Purchase (code P) | Jon Faiz Kayyem (Director) bought 5,000 shares indirectly (by trust) at $100.00 ($500K), reported as a purchase (code P). Holdings by trust up 1% to 429,360 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Sep 17, 2026 |
| Sep 11–15, 2026 | Sale | Kimberly Manhard (Director) sold 1,500 shares indirectly (by trust) between Sep 11 and Sep 15 at about $109.03 ($164K). Holdings by trust down 17% to 7,500 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Sep 15, 2026 |
| Sep 8–9, 2026 | Sale | Kimberly Manhard (Director) sold 1,000 shares indirectly (by trust) between Sep 8 and Sep 9 at about $115.47 ($115K). Holdings by trust down 10% to 9,000 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Sep 10, 2026 |
| Sep 8, 2026 | Purchase (code P) | Jon Faiz Kayyem (Director) bought 5,000 shares indirectly (by trust) at about $113.52 ($568K), reported as a purchase (code P). Holdings by trust up 1% to 424,360 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Sep 8, 2026 |
| Sep 8, 2026 | Purchase (code P) | Mark Lappe (CEO and Director) bought 25,000 shares indirectly (by trust) at about $105.81 ($2.6M), reported as a purchase (code P). Holdings by trust up 4% to 730,548 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Sep 8, 2026 |
| Sep 8, 2026 | Purchase (code P) | Douglas Forsyth (Director) bought 2,500 shares indirectly (by trust) at about $114.65 ($287K), reported as a purchase (code P). Holdings by trust up 1% to 227,064 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Sep 8, 2026 |
5 routine transactions (such as grants, option exercises or tax withholding) are not listed.
Cluster buys
3 insiders bought in 30 days
$6.3M in purchases since Sep 8, 2026 · Purchases traded Sep 8, 2026 to Oct 14, 2026 · Active
| Insider | Value | Traded | Source |
|---|---|---|---|
| Douglas Forsyth (Director) | $287K | Sep 8, 2026 | SEC filing |
| Mark Lappe (CEO) | $2.6M | Sep 8, 2026 | SEC filing |
| Jon Faiz Kayyem (Director) | $568K | Sep 8, 2026 | SEC filing |
| Jon Faiz Kayyem (Director) | $500K | Sep 16, 2026 | SEC filing |
| Jon Faiz Kayyem (Director) | $500K | Sep 23, 2026 | SEC filing |
| Mark Lappe (CEO) | $999K | Sep 28, 2026 | SEC filing |
| Mark Lappe (CEO) | $849K | Oct 14, 2026 | SEC filing |
Red flags
No red flags in the last 12 months.
Key events
No key events in the last 12 months.
8-K filings, last 12 months
No 8-K filings in the last 12 months.
Red flags are objective triggers only: the item or form filed, never an opinion.
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