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

$810.3K

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 $10.41 $355.9K $25.3K 14 2026-06-11
MGNX Director 114,750 $3.96 $454.4K $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 filings
Form 4 transactions across all companies, newest first.
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
Showing 1120 of 53
Page 2 of 6
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.