PLAB's three largest insider shareholders as of August 04, 2026 are Constantine S Macricostas (Executive Chairman, 467.57K shares), Peter S Kirlin (Chief Executive Officer, 438.57K shares), Constantine S Macricostas (Director, 410.89K shares).
| # | Insider | Position | Direct | Indirect | Total | Share of Insiders | Last Filed |
|---|---|---|---|---|---|---|---|
| 1 | Constantine S Macricostas | Director | 878,470 | 0 | 878,470 | 18.5% | 14 Apr, 2026 |
| 2 | Peter S Kirlin | Chief Executive Officer | 838,195 | 0 | 838,195 | 17.7% | 02 Mar, 2022 |
| 3 | Kang Jyh Lee | Chief Executive Officer | 770,450 | 0 | 770,450 | 16.3% | 17 Apr, 2026 |
| 4 | Richelle E Burr | Evp, Cao, Gc Secretary | 540,446 | 0 | 540,446 | 11.4% | 22 May, 2024 |
| 5 | George Macricostas | Ceo | 417,068 | 0 | 417,068 | 8.8% | 10 Apr, 2026 |
| 6 | Christopher J Progler | Evp, Chief Technology Officer | 295,409 | 0 | 295,409 | 6.2% | 16 Dec, 2025 |
| 7 | John P Jordan | Evp, Cfo | 270,902 | 0 | 270,902 | 5.7% | 27 Feb, 2024 |
| 8 | Eric Rivera | President, Cfo | 136,173 | 0 | 136,173 | 2.9% | 15 Apr, 2026 |
| 9 | Daniel Jl Liao | Director | 113,782 | 0 | 113,782 | 2.4% | 22 Jan, 2026 |
| 10 | Hsueh-Chun Wang | Svp/Coo Ic Us/Eu Mnstrm Ops | 113,560 | 0 | 113,560 | 2.4% | 16 Apr, 2026 |
| 11 | Mitchell G Tyson | Director | 108,300 | 0 | 108,300 | 2.3% | 15 Apr, 2026 |
| 12 | Han Kyung Park | Svp Gm Of Fpd Ops | 75,500 | 0 | 75,500 | 1.6% | 20 Jan, 2026 |
| 13 | Adam M Lewis | Director | 61,792 | 0 | 61,792 | 1.3% | 15 Apr, 2026 |
| 14 | Walter M Fiederowicz | Other | 52,000 | 0 | 52,000 | 1.1% | 17 Apr, 2025 |
| 15 | Rui Zhang | Vp, Cao Corporate Controller | 27,079 | 0 | 27,079 | 0.6% | 21 Apr, 2026 |
| 16 | Todd Anthony Alesio | Svp, Cao | 17,946 | 0 | 17,946 | 0.4% | 11 Feb, 2026 |
| 17 | David A. Garcia | Director | 15,192 | 0 | 15,192 | 0.3% | 15 Apr, 2026 |
| 18 | Michelle Almeida | Director | 4,956 | 0 | 4,956 | 0.1% | 15 Apr, 2026 |
| 19 | Mary Paladino | Director | 1,272 | 0 | 1,272 | 0.0% | 21 Apr, 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 |
|---|---|---|---|---|---|---|---|---|
| 17 Apr, 2026 | Rui Zhang | Vp, Cao Corporate Controller | Disposed S | 4,556 | $46.70 | $212.77K | 27,079 | Direct |
| 17 Apr, 2026 | Rui Zhang | Vp, Cao Corporate Controller | Disposed S | 4,556 | $46.70 | $212.77K | 27,079 | Direct |
| 17 Apr, 2026 | Mary Paladino | Director | Disposed D | 22,548 | $47.77 | $1.08Mn | 1,272 | Direct |
| 17 Apr, 2026 | Rui Zhang | Vp, Cao Corporate Controller | Disposed S | 4,556 | $46.70 | $212.77K | 27,079 | Direct |
| 15 Apr, 2026 | Kang Jyh Lee | Director | Disposed S | 10,000 | $45.10 | $451.00K | 375,850 | Direct |
| 14 Apr, 2026 | Hsueh-Chun Wang | Svp/Coo Ic Us/Eu Mnstrm Ops | Disposed S | 19,250 | $45.30 | $872.03K | 113,560 | Direct |
| 13 Apr, 2026 | Mitchell G Tyson | Director | Acquired A | 3,722 | $0.00 | $0 | 36,921 | Direct |
| 13 Apr, 2026 | Eric Rivera | President, Cfo | Acquired M | 1,000 | $9.78 | $9.78K | 137,173 | Direct |
| 13 Apr, 2026 | Mitchell G Tyson | Director | Acquired A | 3,722 | $0.00 | $0 | 36,921 | Direct |
| 13 Apr, 2026 | Adam M Lewis | Director | Acquired A | 3,722 | $0.00 | $0 | 34,792 | Direct |
| 13 Apr, 2026 | Mitchell G Tyson | Director | Acquired A | 3,722 | $0.00 | $0 | 36,921 | Direct |
| 13 Apr, 2026 | Michelle Almeida | Director | Acquired A | 3,722 | $0.00 | $0 | 4,956 | Direct |
| 13 Apr, 2026 | Mitchell G Tyson | Director | Acquired A | 3,722 | $0.00 | $0 | 36,921 | Direct |
| 13 Apr, 2026 | David A. Garcia | Director | Acquired A | 3,722 | $0.00 | $0 | 15,192 | Direct |
| 13 Apr, 2026 | Mitchell G Tyson | Director | Acquired A | 3,722 | $0.00 | $0 | 36,921 | Direct |
| 13 Apr, 2026 | Eric Rivera | President, Cfo | Disposed S | 1,000 | $44.77 | $44.77K | 136,173 | Direct |
| 13 Apr, 2026 | Eric Rivera | President, Cfo | Disposed M | 1,000 | $0.00 | $0 | 0 | Direct |
| 01 Apr, 2026 | Constantine S Macricostas | Director | Disposed G | 13,000 | $0.00 | $0 | 447,895 | Direct |
| 14 Apr, 2026 | Constantine S Macricostas | Director | Disposed S | 50,000 | $45.35 | $2.27Mn | 0 | Indirect |
| 02 Apr, 2026 | Constantine S Macricostas | Director | Disposed G | 37,000 | $0.00 | $0 | 410,895 | Direct |