Insider profile
Mark N Lampert Insider Trading
This page tracks every SEC Form 4 filing since April 2023 by Mark N Lampert: 174 transactions in total, including 44 open-market purchases and 25 sales. Each record is parsed directly from the original filing, with amendments reconciled so a corrected filing never double-counts.
- Role
- Director
- CIK
- 0001233840
- Companies traded
- 3
- Total filings
- 174
- First filing
- 2023-04-05
- Last filing
- 2026-09-16
Files as LAMPERT MARK N · SEC EDGAR ↗
Activity summary
The most recent open-market decision, on June 26, 2026, was 4 sales totaling 1,630,658 shares ($173.7M).
Three year balance
Buy and sell value by quarter, Q4 23 to Q3 26. Mark N Lampert has been a net seller across the period shown.
Bars below the rule are sales, above are purchases. Largest quarter on the chart is $213.7M.
Insider insight
Mark N Lampert trades most actively in KYMR, accounting for 7 of the 174 filings on record. The largest single open-market purchase on record is $6.3M in KYMR, filed Jun 2025.
Track record
Most active in
Avg buy vs sell price
Average prices across open-market transactions in this dataset.
Transaction History
Sourced from SEC EDGAR Form 4 filings. Updated hourly.
| Date | Insider | Company | Type | Shares | Price | Value |
|---|---|---|---|---|---|---|
| Sep 16, 2026 | Mark N Lampert | IMUX | Award | 25,370 | — | — |
| Jul 14, 2026 | Mark N Lampert | XOMA | U | 2,773,545 | — | — |
| Jul 14, 2026 | Mark N Lampert | XOMA | U | 3,635,758 | — | — |
| Jul 14, 2026 | Mark N Lampert | XOMA | U | 772,000 | — | — |
| Jul 14, 2026 | Mark N Lampert | XOMA | U | 412,000 | — | — |
45 more transactions hidden
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The same rows, over the API.
curl "https://api.form4api.com/v1/insiders/0001233840/transactions" \
-H "X-Api-Key: $KEY"Companies traded
By number of filings.
Based on the last 50 filings on file — this insider has a longer history.
Filing cadence
Filings per quarter, this window.
Busiest: Q2 26 (15 filings)
Quietest: Q4 25 (3 filings)
Based on the last 50 filings on file — this insider has a longer history.
Reading an insider's Form 4 history
Corporate insiders — directors, officers, and holders of more than 10% of a company's stock — must report their trades to the SEC on Form 4 within two business days. Looking at one insider's filings over time shows whether they tend to buy on the open market (a discretionary use of their own money, generally the strongest signal), sell, or simply receive and exercise equity awards as compensation.
The track record above measures how this insider's past open-market purchases performed in the months after each filing. Trades made under a pre-scheduled Rule 10b5-1 plan are flagged because they carry no timing signal. To pull any insider's full history programmatically, see the insider trading API or our guide to reading Form 4 filings.