WILLIAM K HEIDEN
CIK 1214939 · President & CEO · last filed 2026-06-11
"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
$708.8K
Companies
4
Total Filings
53
Lifetime Open-Market Net
-$6.99M
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.
| Symbol | Role | Shares | Price | Disclosed Exposure | Lifetime OM Net | Filings | Latest Filed |
|---|---|---|---|---|---|---|---|
| ATRA | Director | 34,188 | $7.81 | $267.0K | $25.3K | 14 | 2026-06-11 |
| MGNX | Director | 114,750 | $3.85 | $441.8K | $150.5K | 7 | 2026-05-20 |
| AMAG PHARMACEUTICALS, INC. (AMAG) Delisted | President & CEO | 424,612 | — | — | -$7.16M | 30 | 2020-03-04 |
| GTC BIOTHERAPEUTICS INC (GTCB) Delisted | Director | — | — | — | $0 | 1 | 2009-10-05 |
Recent Filings · Page 2 of 6
53 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 |
|---|---|---|---|---|---|
| 2023-06-02 | ATRA | Grant (A) | +57,000 | $0 | EDGAR |
| 2022-06-27 | ATRA | Grant (A) | +20,500 | $0 | EDGAR |
| 2022-05-24 | MGNX | Grant (A) | — | $0 | EDGAR |
| 2021-06-09 | ATRA | Grant (A) | +11,000 | $0 | EDGAR |
| 2020-06-17 | ATRA | Grant (A) | +8,000 | $0 | EDGAR |
| 2020-03-04 | AMAG PHARMACEUTICALS, INC. (AMAG) Delisted | Tax (F) | −4,451 | -$34.5K | EDGAR |
| 2020-02-25 | AMAG PHARMACEUTICALS, INC. (AMAG) Delisted | Tax (F) | −5,993 | -$54.9K | EDGAR |
| 2019-07-01 | ATRA | Grant (A) | +4,000 | $0 | EDGAR |
| 2019-05-09 | AMAG PHARMACEUTICALS, INC. (AMAG) Delisted | Buy (P) | +10,000 | $107.0K | EDGAR |
| 2019-03-05 | AMAG PHARMACEUTICALS, INC. (AMAG) Delisted | Tax (F) | −8,002 | -$118.1K | 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.