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David Y Liu

CIK 1675881 · Chief R&D Strategy Officer · last filed 2022-11-17

David Y Liu is a Chief R&D Strategy Officer who has filed 19 SEC Form 4 insider transactions across 1 company since 2016. The most recent filing shows the insider exercised options covering $231.8K of PTGX on Nov 17, 2022. Across all open-market trades the lifetime net is −$1.1M, making them a net seller over the disclosed history. Current disclosed insider exposure totals $13.6M 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

$13.61M

Companies

1

Total Filings

19

Lifetime Open-Market Net

-$1.07M

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 Chief R&D Strategy Officer 96,603 $140.91 $13.61M -$1.07M 19 2022-11-17

Recent Filings

19 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
2022-11-17 PTGX Exer (M) +100,479 $231.8K EDGAR
2022-03-02 PTGX Tax (F) −2,119 -$51.4K EDGAR
2022-02-17 PTGX Grant (A) +10,000 $0 EDGAR
2021-08-19 PTGX Mixed −4,779 -$694.2K EDGAR
2021-02-26 PTGX Grant (A) +10,000 $0 EDGAR
2020-02-28 PTGX Grant (A) — $0 EDGAR
2019-08-08 PTGX Sell (S) −3,395 -$30.0K EDGAR
2019-03-04 PTGX Mixed +14,190 -$6.5K EDGAR
2019-02-08 PTGX Sell (S) −3,821 -$29.6K EDGAR
2018-08-17 PTGX Grant (A) +25,800 $0 EDGAR
Showing 1–10 of 19
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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.