Onto Innovation's top three insider shareholders as of September 09, 2026 are Michael P Plisinski (Chief Executive Officer, 179.24K shares), Michael P Plisinski (Chief Executive Officer, 179.24K shares), Michael P Plisinski (Chief Executive Officer, 179.24K shares).
| # | Insider | Position | Direct | Indirect | Total | Share of Insiders | Last Filed |
|---|---|---|---|---|---|---|---|
| 1 | Michael P Plisinski | Chief Executive Officer | 179,242 | 0 | 179,242 | 35.2% | 04 Mar, 2026 |
| 2 | Christine A Tsingos | Director | 42,918 | 0 | 42,918 | 8.4% | 23 May, 2024 |
| 3 | Christopher A Seams | Director | 38,513 | 0 | 38,513 | 7.6% | 22 May, 2026 |
| 4 | Ido Dolev | Evp, Prod Solutions Grp | 26,536 | 0 | 26,536 | 5.2% | 04 Mar, 2026 |
| 5 | Steven R Roth | Sr Vp Cfo | 23,043 | 0 | 23,043 | 4.5% | 13 Feb, 2022 |
| 6 | Yoon Ah Oh | Svp, Gen Counsel Corp Sec | 21,110 | 0 | 21,110 | 4.1% | 18 May, 2026 |
| 7 | Brian K Roberts | Chief Financial Officer | 21,032 | 0 | 21,032 | 4.1% | 04 Sep, 2026 |
| 8 | Leo Berlinghieri | Director | 20,210 | 0 | 20,210 | 4.0% | 23 May, 2024 |
| 9 | Srinivas Vedula | Svp, Customer Success | 18,730 | 0 | 18,730 | 3.7% | 05 Mar, 2025 |
| 10 | Ramil Yaldaei | Chief Operating Officer | 17,593 | 0 | 17,593 | 3.5% | 18 May, 2026 |
| 11 | Shirley Chen | Senior Vice President Of Custo | 14,001 | 0 | 14,001 | 2.8% | 04 Sep, 2026 |
| 12 | Mark Slicer | Chief Financial Officer | 13,640 | 0 | 13,640 | 2.7% | 19 May, 2025 |
| 13 | David Brian Miller | Director | 12,692 | 0 | 12,692 | 2.5% | 22 May, 2026 |
| 14 | Ju Jin | Svp Gm, Ibu | 10,254 | 0 | 10,254 | 2.0% | 16 Jun, 2023 |
| 15 | Robert Fiordalice | Svp Gm, Metrology Bu | 8,763 | 0 | 8,763 | 1.7% | 05 Mar, 2024 |
| 16 | James Harlow | Chief Operating Officer | 8,586 | 0 | 8,586 | 1.7% | 15 Feb, 2023 |
| 17 | May Su | Director | 7,984 | 0 | 7,984 | 1.6% | 22 May, 2026 |
| 18 | Stephen Douglas Kelley | Director | 6,384 | 0 | 6,384 | 1.3% | 22 May, 2026 |
| 19 | Karen M Rogge | Director | 5,150 | 0 | 5,150 | 1.0% | 11 May, 2023 |
| 20 | Stephen S Schwartz | Director | 3,536 | 0 | 3,536 | 0.7% | 22 May, 2026 |
| 21 | Bruce C Rhine | Director | 3,500 | 0 | 3,500 | 0.7% | 17 Feb, 2022 |
| 22 | D Mayson Brooks | Vice President Gm, Ibu | 3,025 | 0 | 3,025 | 0.6% | 04 Sep, 2024 |
| 23 | Susan D Lynch | Director | 2,684 | 0 | 2,684 | 0.5% | 25 Aug, 2026 |
Each row is that insider’s most recently reported position, from Form 4 filings over the last 60 months — which is why this total does not tie to the quarterly series above, where a quarter counts only the insiders who filed in it. Shares held through a fund or institutional portfolio are counted on the institutional ownership page instead.
| Date | Insider | Position | Transaction | Shares | Price | Value | Shares Held After | Ownership |
|---|---|---|---|---|---|---|---|---|
| 02 Sep, 2026 | Brian K Roberts | Chief Financial Officer | Disposed F | 3,239 | $254.55 | $824.49K | 21,032 | Direct |
| 02 Sep, 2026 | Shirley Chen | Senior Vice President Of Custo | Disposed F | 1,516 | $254.55 | $385.90K | 14,001 | Direct |
| 02 Sep, 2026 | Brian K Roberts | Chief Financial Officer | Disposed F | 3,239 | $254.55 | $824.49K | 21,032 | Direct |
| 21 Aug, 2026 | Susan D Lynch | Director | Disposed S | 1,000 | $302.30 | $302.30K | 2,684 | Direct |
| 20 May, 2026 | Stephen S Schwartz | Director | Acquired A | 761 | $0.00 | $0 | 3,536 | Direct |
| 20 May, 2026 | Christopher A Seams | Director | Acquired A | 761 | $0.00 | $0 | 38,513 | Direct |
| 20 May, 2026 | David Brian Miller | Director | Acquired A | 761 | $0.00 | $0 | 12,692 | Direct |
| 20 May, 2026 | Susan D Lynch | Director | Acquired A | 761 | $0.00 | $0 | 3,684 | Direct |
| 20 May, 2026 | Stephen Douglas Kelley | Director | Acquired A | 761 | $0.00 | $0 | 6,384 | Direct |
| 20 May, 2026 | May Su | Director | Acquired A | 761 | $0.00 | $0 | 7,984 | Direct |
| 15 May, 2026 | Ramil Yaldaei | Chief Operating Officer | Disposed F | 218 | $271.77 | $59.25K | 18,218 | Direct |
| 15 May, 2026 | Yoon Ah Oh | Svp, Gen Counsel Corp Sec | Disposed F | 530 | $271.77 | $144.04K | 21,110 | Direct |
| 15 May, 2026 | Ramil Yaldaei | Chief Operating Officer | Disposed F | 625 | $271.77 | $169.86K | 17,593 | Direct |
| 02 Mar, 2026 | Ido Dolev | Evp, Prod Solutions Grp | Acquired A | 3,440 | $0.00 | $0 | 27,355 | Direct |
| 02 Mar, 2026 | Ramil Yaldaei | Chief Operating Officer | Acquired A | 7,683 | $0.00 | $0 | 19,051 | Direct |
| 02 Mar, 2026 | Ramil Yaldaei | Chief Operating Officer | Acquired A | 7,683 | $0.00 | $0 | 19,051 | Direct |
| 02 Mar, 2026 | Yoon Ah Oh | Svp, Gen Counsel Corp Sec | Acquired A | 2,408 | $0.00 | $0 | 22,057 | Direct |
| 02 Mar, 2026 | Michael P Plisinski | Chief Executive Officer | Acquired A | 14,479 | $0.00 | $0 | 182,984 | Direct |
| 02 Mar, 2026 | Ramil Yaldaei | Chief Operating Officer | Acquired A | 7,683 | $0.00 | $0 | 19,051 | Direct |
| 02 Mar, 2026 | Ramil Yaldaei | Chief Operating Officer | Acquired A | 7,683 | $0.00 | $0 | 19,051 | Direct |