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.

Loading insider history…
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 3 of 6

53 filings
Insider 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
2019-02-27 AMAG PHARMACEUTICALS, INC. (AMAG) Delisted Grant (A) +163,000 $0 EDGAR
2019-02-26 AMAG PHARMACEUTICALS, INC. (AMAG) Delisted Tax (F) −2,957 -$45.9K EDGAR
2018-08-08 AMAG PHARMACEUTICALS, INC. (AMAG) Delisted Sell (S) −5,000 -$125.0K EDGAR
2018-06-18 ATRA Grant (A) +1,500 $0 EDGAR
2018-06-05 AMAG PHARMACEUTICALS, INC. (AMAG) Delisted Sell (S) −20,000 -$500.0K EDGAR
2018-03-06 AMAG PHARMACEUTICALS, INC. (AMAG) Delisted Mixed +80,454 -$221.5K EDGAR
2017-06-12 ATRA Grant (A) +5,000 $0 EDGAR
2017-05-10 AMAG PHARMACEUTICALS, INC. (AMAG) Delisted Tax (F) −19,085 -$354.0K EDGAR
2017-02-27 AMAG PHARMACEUTICALS, INC. (AMAG) Delisted Grant (A) +85,000 $0 EDGAR
2017-01-05 ATRA Grant (A) +2,000 $0 EDGAR
Showing 2130 of 53
Page 3 of 6
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.