Mark N. Tompkins
CIK 1455971 · last filed 2026-05-27
"Disclosed insider exposure" sums this person's most-recently-reported share counts across each company they're an insider in, multiplied by the current underlying price. It is not net worth — it misses retail holdings, private investments, real estate, index funds, and any company where the person isn't an SEC-reporting insider. For informational purposes only.
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Disclosed Exposure
$75.82M
Companies
3
Total Filings
62
Lifetime Open-Market Net
-$23.81M
Holdings By Company
Latest on-record share count from this person's most recent non-derivative Form 4 transaction in each company. Disclosed exposure = shares × current underlying price.
Recent Filings · Page 5 of 7
62 filingsInsider activity across all companies, newest first. Form 4 rows are post-trade confirmations (buys, sells, grants, exercises). Notice (144) rows are pre-trade notices of intent to sell restricted or control stock under Rule 144 — they may not all execute. Compare adjacent dates to see which notices became actual sales.
| Filed | Symbol | Action | Net Shares | Net $ | Link |
|---|---|---|---|---|---|
| 2021-04-07 | AMST | Sell (S) | −77,828 | -$326.3K | EDGAR |
| 2021-04-01 | AMST | Sell (S) | −86,511 | -$364.4K | EDGAR |
| 2021-03-05 | AMST | Sell (S) | −20,000 | -$112.5K | EDGAR |
| 2021-02-25 | — | Other (J) | −2,450,000 | $0 | |
| 2020-10-07 | — | Other (J) | −2,760,000 | $0 | |
| 2020-09-29 | AMST | Buy (P) | +20,000 | $100.0K | EDGAR |
| 2020-02-14 | — | Mixed | −632,699 | $100.0K | |
| 2018-09-06 | — | Sell (S) | −50,000 | -$4.0K | |
| 2018-05-01 | — | Grant (A) | +83,334 | $100.0K | |
| 2017-12-29 | AKTS | Sell (S) | −30,581 | -$187.6K | EDGAR |
Form 4 codes: P = open-market purchase · S = open-market sale · A = grant/award · M = option exercise · F = tax withholding at vest · G = bona-fide gift · D = disposition to issuer · J = other (see filing footnote). Only P / S codes carry directional signal.
Notice (144 / 144/A): Form 144 is a notice of intent to sell restricted/control stock under Rule 144, filed before the sale; 144/A is an amendment. Many notices are pre-scheduled under Rule 10b5-1 plans. A Form 4 with code S typically follows within a few days when the planned sale executes; missing follow-up Form 4s suggest the notice was cancelled or modified.
Notice (144 / 144/A): Form 144 is a notice of intent to sell restricted/control stock under Rule 144, filed before the sale; 144/A is an amendment. Many notices are pre-scheduled under Rule 10b5-1 plans. A Form 4 with code S typically follows within a few days when the planned sale executes; missing follow-up Form 4s suggest the notice was cancelled or modified.