OH Yoon Ah
Officer · ONTO
As of 2026-09-16, OH Yoon Ah has 25 Form 4 transactions on record across 1 company — 12 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.
Reconstructed holdings
- Direct $5.1M
- Indirect $0
| ONTO | direct | 21,110 sh | $5.1M |
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 |
|---|
25 award / exercise / gift records — not counted as purchases
| Date | Company | Action | Shares | Owned after | Filing |
|---|---|---|---|---|---|
| 2026-05-15 | ONTO | Withheld for tax | 530 | 21,110 | Form 4 |
| 2026-03-03 | ONTO | Withheld for tax | 417 | 21,640 | Form 4 |
| 2026-03-02 | ONTO | Award / grant | 2,408 | 22,057 | Form 4 |
| 2026-03-02 | ONTO | Award / grant | 1,204 | 1,204 | Form 4 |
| 2026-03-01 | ONTO | Withheld for tax | 307 | 19,916 | Form 4 |
| 2026-03-01 | ONTO | Withheld for tax | 267 | 19,649 | Form 4 |
| 2026-03-01 | ONTO | Option exercise | 941 | 0 | Form 4 |
| 2026-03-01 | ONTO | Option exercise | 724 | 20,223 | Form 4 |
| 2026-02-14 | ONTO | Withheld for tax | 1,094 | 20,000 | Form 4 |
| 2026-02-14 | ONTO | Withheld for tax | 501 | 19,499 | Form 4 |
| 2026-02-14 | ONTO | Option exercise | 1,977 | 0 | Form 4 |
| 2026-02-14 | ONTO | Option exercise | 3,084 | 21,094 | Form 4 |
| 2025-05-15 | ONTO | Withheld for tax | 603 | 18,010 | Form 4 |
| 2025-03-03 | ONTO | Award / grant | 1,470 | 1,470 | Form 4 |
| 2025-03-03 | ONTO | Award / grant | 1,471 | 1,471 | Form 4 |
| 2025-03-03 | ONTO | Award / grant | 2,941 | 18,613 | Form 4 |
| 2025-03-01 | ONTO | Withheld for tax | 304 | 15,672 | Form 4 |
| 2025-02-14 | ONTO | Withheld for tax | 1,830 | 16,469 | Form 4 |
| 2025-02-14 | ONTO | Withheld for tax | 493 | 15,976 | Form 4 |
| 2025-02-14 | ONTO | Option exercise | 3,956 | 18,299 | Form 4 |
| 2025-02-14 | ONTO | Option exercise | 1,978 | 0 | Form 4 |
| 2025-02-10 | ONTO | Withheld for tax | 1,016 | 11,623 | Form 4 |
| 2025-02-10 | ONTO | Withheld for tax | 375 | 12,639 | Form 4 |
| 2025-02-10 | ONTO | Option exercise | 2,720 | 14,343 | Form 4 |
| 2025-02-10 | ONTO | Option exercise | 1,360 | 0 | 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.