SEC Form 4 reporting owner

Zhang Shuo

Zhang Shuo has filed 6 Form 4 transactions reported between December 15, 2025 and August 12, 2026, as Director of PDF SOLUTIONS INC and Director of GRID DYNAMICS HOLDINGS, INC..

Name as filed: Zhang Shuo

Open-market buys, 24 mo
None
reported
Open-market sales, 24 mo
$107K
2 lines
Companies
2
with Form 4 filings
Latest transaction
Aug 12, 2026
transaction date

Roles and reported holdings

  • PDFSPDF SOLUTIONS INC
    Jul 1, 2026 – Aug 12, 2026

    Director

    Held directly23,380 sh as of Aug 12, 2026 · Form 4

    24 months: $77K sold

  • GDYNGRID DYNAMICS HOLDINGS, INC.
    Dec 15, 2025 – Aug 7, 2026

    Director

    Held directly104,772 sh as of Aug 7, 2026 · Form 4

    24 months: $29K sold

Transaction history

All 6 reported transactions, newest first. Every row links to the Form 4 on SEC EDGAR.

DateCompanyTypeSharesValueFiling
Aug 12, 2026PDFSDirectorOpen-market saleCode S · direct1,501$77K@ $51.47Form 4
Aug 7, 2026GDYNDirectorGiftCode G · direct5,134—Form 4
Jul 1, 2026PDFSDirectorGrant or awardCode A · direct2,689—Form 4
Dec 23, 2025GDYNGrant or awardCode A · direct5,978—Form 4
Dec 23, 2025GDYNGrant or awardCode A · direct11,413—Form 4
Dec 15, 2025GDYNOpen-market saleCode S · direct3,000$29K@ $9.75Form 4

How this page is built

Every row comes from a Form 4 filed with the SEC, which officers, directors and holders of more than 10% of a company’s stock must file within two business days of a trade. Transactions are grouped by the reporting owner’s name as filed (spacing, capitals and punctuation ignored); two different people filing under an identical name would appear together, and one person filing under two spellings appears on two pages.

Open-market totals count code P purchases and code S sales over the last 24 months. The same trade reported on more than one filing is counted once; when another owner (for example a fund and its general partner) reports the identical trade, they are listed beside it. Holdings are the shares owned after the latest purchase, sale, gift or tax-withholding line, shown separately for direct and indirect ownership; an indirect figure is one holding line, not a total across every trust or entity.

This page describes what was filed with the SEC; it is not investment advice or a recommendation to buy or sell any security.