Zhang John Z
Officer · GLW
As of 2026-09-27, Zhang John Z has 52 Form 4 transactions on record across 1 company — 15 in the trailing 12 months.
Everything this person has disclosed to the SEC on Form 4 — across every company they file for — reconstructed from the public record. A filing history, not a tip sheet.
Pattern in the record: open-market sales filed in May in multiple years since 2024 — a recurring calendar cadence, more consistent with scheduled activity than a one-off decision.
Reconstructed holdings
- Direct $805K
- Indirect $0
| GLW | direct | 5,138 sh | $805K |
Reconstructed from this person's own Form 4 filings — the total each filing reported owning afterward, priced at the close on the as-of date shown. A filed position can lag the real one.
Direct and indirect holdings (e.g. through a trust or fund) are tagged separately, as filed.
Trades by company
Filing ledger
| Date | Company | Action | Shares @ price | Value | Ownership Δ | Owned after | Filing |
|---|---|---|---|---|---|---|---|
| 2026-05-11 | GLW | Sale | 10,000 @ $198.34 | $2.0M | −66.1% of holding | 5,138 | Form 4 |
| 2026-05-06 | GLW | Sale | 15,000 @ $184.67 | $2.8M | −49.8% of holding | 15,138 | Form 4 |
| 2026-02-12 | GLW | Sale | 1,531 @ $133.75 | $205K | −100.0% of holding | 0 | Form 4 |
| 2025-08-12 | GLW | Sale | 1,212 @ $65.53 | $79K | −100.0% of holding | 0 | Form 4 |
| 2025-05-28 | GLW | Sale | 9,610 @ $49.29 | $474K | −100.0% of holding | 0 | Form 4 |
| 2025-05-12 | GLW | Sale | 8,000 @ $46.91 | $375K | −45.4% of holding | 9,610 | Form 4 |
| 2025-02-18 | GLW | Sale | 14,111 @ $52.78 | $745K | −100.0% of holding | 0 | Form 4 |
| 2024-11-13 | GLW | Sale | 5,175 @ $48.36 | $250K | −100.0% of holding | 0 | Form 4 |
| 2024-08-13 | GLW | Sale | 12,918 @ $39.73 | $513K | −100.0% of holding | 0 | Form 4 |
| 2024-05-02 | GLW | Sale | 12,546 @ $33.42 | $419K | −52.5% of holding | 11,355 | Form 4 |
| 2024-02-15 | GLW | Sale | 6,607 @ $32.02 | $212K | −34.5% of holding | 12,546 | Form 4 |
41 award / exercise / gift records — not counted as purchases
| Date | Company | Action | Shares | Owned after | Filing |
|---|---|---|---|---|---|
| 2026-04-15 | GLW | Withheld for tax | 31,433 | 30,138 | Form 4 |
| 2026-04-15 | GLW | Option exercise | 18,884 | 61,571 | Form 4 |
| 2026-04-15 | GLW | Option exercise | 42,687 | 0 | Form 4 |
| 2026-04-15 | GLW | Option exercise | 18,884 | 0 | Form 4 |
| 2026-04-15 | GLW | Option exercise | 42,687 | 42,687 | Form 4 |
| 2026-04-01 | GLW | Award / grant | 9,692 | 9,692 | Form 4 |
| 2026-02-09 | GLW | Withheld for tax | 945 | 1,531 | Form 4 |
| 2026-02-09 | GLW | Option exercise | 2,476 | 0 | Form 4 |
| 2026-02-09 | GLW | Option exercise | 2,476 | 2,476 | Form 4 |
| 2026-02-04 | GLW | Award / grant | 16,891 | 16,891 | Form 4 |
| 2026-02-04 | GLW | Award / grant | 20,932 | 42,687 | Form 4 |
| 2026-02-04 | GLW | Award / grant | 15,591 | 35,839 | Form 4 |
| 2025-08-08 | GLW | Withheld for tax | 1,264 | 1,212 | Form 4 |
| 2025-08-08 | GLW | Option exercise | 2,476 | 2,476 | Form 4 |
| 2025-04-15 | GLW | Withheld for tax | 18,368 | 17,610 | Form 4 |
| 2025-04-15 | GLW | Option exercise | 14,439 | 35,978 | Form 4 |
| 2025-04-15 | GLW | Option exercise | 14,439 | 0 | Form 4 |
| 2025-04-15 | GLW | Option exercise | 21,539 | 0 | Form 4 |
| 2025-04-15 | GLW | Option exercise | 21,539 | 21,539 | Form 4 |
| 2025-04-01 | GLW | Award / grant | 24,374 | 24,374 | Form 4 |
| 2025-02-18 | GLW | Option exercise | 12,529 | 14,111 | Form 4 |
| 2025-02-18 | GLW | Option exercise | 12,529 | 0 | Form 4 |
| 2025-02-10 | GLW | Withheld for tax | 893 | 1,582 | Form 4 |
| 2025-02-10 | GLW | Option exercise | 2,475 | 2,475 | Form 4 |
| 2025-02-10 | GLW | Option exercise | 2,475 | 4,952 | Form 4 |
| 2025-02-04 | GLW | Award / grant | 14,717 | 21,539 | Form 4 |
| 2025-02-04 | GLW | Award / grant | 16,996 | 21,755 | Form 4 |
| 2025-02-04 | GLW | Award / grant | 20,248 | 20,248 | Form 4 |
| 2024-11-13 | GLW | Option exercise | 5,175 | 5,175 | Form 4 |
| 2024-11-13 | GLW | Option exercise | 5,175 | 0 | Form 4 |
| 2024-08-08 | GLW | Withheld for tax | 1,633 | 12,918 | Form 4 |
| 2024-08-08 | GLW | Option exercise | 2,475 | 13,830 | Form 4 |
| 2024-08-08 | GLW | Option exercise | 721 | 0 | Form 4 |
| 2024-08-08 | GLW | Option exercise | 2,475 | 7,427 | Form 4 |
| 2024-08-08 | GLW | Option exercise | 721 | 14,551 | Form 4 |
| 2024-04-15 | GLW | Withheld for tax | 11,845 | 23,901 | Form 4 |
| 2024-04-15 | GLW | Option exercise | 13,652 | 35,746 | Form 4 |
| 2024-04-15 | GLW | Option exercise | 13,652 | 0 | Form 4 |
| 2024-04-15 | GLW | Option exercise | 9,548 | 0 | Form 4 |
| 2024-04-15 | GLW | Option exercise | 9,548 | 22,094 | Form 4 |
Source: SEC Form 4 filings. Each row links to its original filing.
Research tool, not investment advice — historical frequencies, not recommendations. A product of Marovel Technologies LLC. Full terms.