Lewis T Williams

CIK 1475714 · Executive Chairman · last filed 2026-02-18

Lewis T Williams is an Executive Chairman who has filed 69 SEC Form 4 insider transactions across 6 companies since 2009. The most recent filing, for PTGX, was dated Feb 18, 2026. Across all open-market trades the lifetime net is −$16.5M, making them a net seller over the disclosed history. Current disclosed insider exposure totals $2.8M across reported positions.

"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

$2.84M

Companies

6

Total Filings

69

Lifetime Open-Market Net

-$16.49M

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
PTGX Director 25,825 $109.78 $2.84M -$1.48M 11 2026-02-18
Arcellx, Inc. (ACLX) Delisted Director 2,095,114 $115.07 $241.08M $0 1 2022-02-09
Neurogene Inc. (NLTX) Delisted Director $13.96 $0 3 2021-05-13
FIVE PRIME THERAPEUTICS, INC. (XLRN) Delisted Director 455,336 $178.75 $81.39M -$1.51M 19 2019-09-04
FIVE PRIME THERAPEUTICS, INC. (FPRX) Delisted President, CEO and Chairman 421,828 $38.00 $16.03M -$13.49M 20 2016-05-13
BECKMAN COULTER INC (BEC) Delisted Director 1,372 $0 14 2011-06-22

Recent Filings

69 filings
Form 4 transactions across all companies, newest first.
Filed Symbol Action Net Shares Net $ Link
2026-02-18 PTGX Mixed -$1.29M EDGAR
2026-01-06 PTGX Grant (A) +2,695 $0 EDGAR
2025-01-06 PTGX Grant (A) +5,130 $0 EDGAR
2024-01-04 PTGX Grant (A) $0 EDGAR
2023-01-18 PTGX Grant (A) $0 EDGAR
2022-05-27 PTGX Grant (A) $0 EDGAR
2022-02-09 Arcellx, Inc. (ACLX) Delisted Conv (C) +2,095,114 $0 EDGAR
2021-05-28 PTGX Grant (A) $0 EDGAR
2021-05-13 Neurogene Inc. (NLTX) Delisted Grant (A) $0 EDGAR
2020-05-29 PTGX Grant (A) $0 EDGAR
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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.