Wednesday, October 28, 2026
Data from SEC filings, checked daily
Public filings, plainly told
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INBX Insider Trading and Fund Holdings (Inhibrx Biosciences, Inc.) · https://wallstpal.com/stock/inbx/ · saved 2026-10-28

About this page

Insider trades reported on SEC Form 4: when the people who run a company buy or sell its shares with their own money.

How to read it

Form 4
The form a company insider (officer, director or owner of more than 10%) must file with the SEC within two business days of buying or selling the company's shares.
Buy (P) and Sell (S)
Open-market purchases and sales. Gifts, option exercises and automatic tax withholding are left out because they say little about what the insider thinks.
Value
Shares times price, as reported on the filing.
10b5-1
A trade made under a plan set up in advance. Planned sales are common and usually say less than an unplanned purchase.
Late filing
A Form 4 filed more than two business days after the trade.
Vs. S&P 500
How the stock did after the trade minus how the overall market did in the same weeks.

A real example

In January 2016, when bank stocks were falling, JPMorgan Chase CEO Jamie Dimon bought 500,000 JPMorgan shares with his own money, worth about $26 million. His Form 4 made the purchase public within days, and investors read it as a strong sign of confidence.

Explain it like I'm 13

If the coach of a team bets his own allowance that his team will win, that tells you something. A Form 4 is the note a company boss must hand in whenever he buys or sells his own company's shares, so everyone can see it.

Data from public SEC filings and congressional reports. Information, not investment advice. Check every number against the filing linked on the page.

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StockCIK 2007919

Inhibrx Biosciences, Inc. (INBX): Insider Trades and Fund Holdings

In the past 12 months, Inhibrx Biosciences, Inc. insiders reported 8 open-market purchases worth $6.35M and 5 sales worth $279K; 0 of the sales were reported as made under a 10b5-1 trading plan.

8Insider buys, 12 months
$6.35MBought by insiders, 12 months
$279KSold by insiders, 12 months
2Tracked funds holding

Timeline: news and trades

Company filings (8-K), insider trades, notices of planned sales (Form 144), Congress trades and fund moves in the past year, newest first.

  1. Oct 14, 2026Insider buyCEO Mark Lappe bought $848,977
  2. Sep 28, 2026Insider buyCEO Mark Lappe bought $453,426
  3. Sep 25, 2026Insider buyCEO Mark Lappe bought $545,357
  4. Sep 23, 2026Insider buyDirector Jon Faiz Kayyem bought $500,000
  5. Sep 16, 2026Insider buyDirector Jon Faiz Kayyem bought $500,000
  6. Sep 15, 2026Insider saleDirector Kimberly Manhard sold $52,525
  7. Sep 15, 2026Planned saleMANHARD KIMBERLY (director) filed notice to sell about $52,525 around Sep 15, 2026
  8. Sep 14, 2026Insider saleDirector Kimberly Manhard sold $55,130
  9. Sep 14, 2026Planned saleMANHARD KIMBERLY (director) filed notice to sell about $55,130 around Sep 14, 2026
  10. Sep 11, 2026Insider saleDirector Kimberly Manhard sold $55,888
  11. Sep 11, 2026Planned saleMANHARD KIMBERLY (director) filed notice to sell about $55,888 around Sep 11, 2026
  12. Sep 9, 2026Insider saleDirector Kimberly Manhard sold $57,898
  13. Sep 9, 2026Planned saleMANHARD KIMBERLY (director) filed notice to sell about $57,898 around Sep 9, 2026
  14. Sep 8, 2026Insider saleDirector Kimberly Manhard sold $57,570
  15. Sep 8, 2026Insider buyCEO Mark Lappe bought $2.6 million
  16. Sep 8, 2026Insider buyDirector Jon Faiz Kayyem bought $567,580
  17. Sep 8, 2026Insider buyDirector Douglas Forsyth bought $286,617
  18. Sep 8, 2026Planned saleMANHARD KIMBERLY (director) filed notice to sell about $57,570 around Sep 8, 2026
  19. Jun 30, 2026FundViking Global Investors cut 22% in Q2 2026 (13F filed Aug 14, 2026)
  20. Jun 30, 2026FundRenaissance Technologies added 24% in Q2 2026 (13F filed Aug 13, 2026)

Recent insider trades

Open-market purchases (code P) and sales (code S) from Form 4. Grants, option exercises and gifts are not shown. Latest filing: Oct 14, 2026.

Recent INBX insider trades
FiledTradedInsiderRoleTypeSharesPrice ($)ValueScoreHoldingFiling
Oct 14Oct 14Mark LappeCEOCEO (ind.)▲ BUY10,04084.56$849K44+6.3%Form 4 ↗
Sep 28Sep 25Mark LappeCEOCEO (ind.)▲ BUY5,50099.16$545K46+0.8%Form 4 ↗
Sep 28Sep 28Mark LappeCEOCEO (ind.)▲ BUY4,500100.76$453K42+0.6%Form 4 ↗
Sep 23Sep 23Jon Faiz KayyemDirectorDirector (ind.)▲ BUY5,000100.00$500K38+1.2%Form 4 ↗
Sep 17Sep 16Jon Faiz KayyemDirectorDirector (ind.)▲ BUY5,000100.00$500K38+1.2%Form 4 ↗
Sep 15Sep 11Kimberly ManhardDirectorDirector (ind.)▼ SELL500111.78$56K−5.6%Form 4 ↗
Sep 15Sep 14Kimberly ManhardDirectorDirector (ind.)▼ SELL500110.26$55K−5.9%Form 4 ↗
Sep 15Sep 15Kimberly ManhardDirectorDirector (ind.)▼ SELL500105.05$53K−6.3%Form 4 ↗
Sep 10Sep 9Kimberly ManhardDirectorDirector (ind.)▼ SELL500115.80$58K−5.3%Form 4 ↗
Sep 10Sep 8Kimberly ManhardDirectorDirector (ind.)▼ SELL500115.14$58K−5.0%Form 4 ↗
Source: SEC Form 4 filings, retrieved Oct 28, 2026. How we read filings
All 13 INBX insider trades →

Insiders who traded in the past year

InsiderRoleBuysBoughtSellsSoldLatest
Mark LappeCEO4$4.49M0$0Oct 14, 2026
Jon Faiz KayyemDirector3$1.57M0$0Sep 23, 2026
Kimberly ManhardDirector0$05$279KSep 15, 2026
Douglas ForsythDirector1$287K0$0Sep 8, 2026
Strongest purchase, 12 months

49 Mark Lappe (CEO), 2026-09-08. What the score means

Filing quality

A All 13 insider trades reported on time. How it is graded

Tracked funds that report INBX

From each fund's latest 13F. Holdings are as of quarter end and are filed up to 45 days later.

FundQuarterSharesValue% of portfolioChange
Viking Global InvestorsQ2 20261,123,929$106.5M0.30%▼ −21.8%
Renaissance TechnologiesQ2 202662,201$5.89M0.01%▲ +23.9%
Source: SEC Form 13F-HR filings, retrieved Oct 28, 2026. How we read filings

Reading these numbers

Insiders sell for many reasons: taxes, diversification, a house. Purchases with their own money are rarer and are usually read as more informative. A Form 4 is due within two business days of the trade. How to read a Form 4 →