Home

WILLIAM P SCULLY

CIK 1045463 · last filed 2026-09-21

WILLIAM P SCULLY is a corporate insider who has filed 24 SEC Form 4 insider transactions across 2 companies since 2014. The most recent filing shows the insider bought $843.5K of PRTA on Sep 21, 2026. Across all open-market trades the lifetime net is +$8.3M, making them a net buyer over the disclosed history. Current disclosed insider exposure totals $8.4M across reported positions. 5 SEC filings were submitted jointly with CELGENE CORP /DE/.

"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

$8.38M

Companies

2

Total Filings

24

Lifetime Open-Market Net

$8.30M

Filer Profile

Reported Address
771 MANATEE COVE
VERO BEACH, FL 32963
Related Filers
CELGENE CORP /DE/ — 5 joint filings, latest 1999-05-27
Profile details as reported on the filer's SEC submissions — for individual insiders the address is often in care of the issuer. Related filers are identified from jointly filed SEC submissions and shared reported addresses. View filings on SEC EDGAR.

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
PRTA 10%+ Owner 1,010,500 $8.29 $8.38M $7.71M 13 2026-09-21
YIELD10 BIOSCIENCE, INC. (MBLX) Delisted 10%+ Owner 2,933,333 — — $591.1K 11 2016-09-14

Recent Filings

24 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
2026-09-21 PRTA Buy (P) +100,000 $843.5K EDGAR
2026-09-03 PRTA Buy (P) +27,000 $255.7K EDGAR
2026-08-21 PRTA Buy (P) +50,000 $439.4K EDGAR
2026-08-18 PRTA Gift (G) −291,553 $0 EDGAR
2026-08-11 PRTA Gift (G) +251,553 $0 EDGAR
2026-08-10 PRTA Buy (P) +37,500 $323.2K EDGAR
2026-06-18 PRTA Buy (P) +20,000 $158.0K EDGAR
2026-06-16 PRTA Gift (G) −325,000 $0 EDGAR
2026-06-12 PRTA Buy (P) +125,000 $1.02M EDGAR
2026-06-05 PRTA Buy (P) +50,000 $465.3K EDGAR
Showing 1–10 of 24
Page 1 of 3
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.