John Tseng-Chung Lee
John Tseng-Chung Lee: President & CEO · Director at MKS. What John Tseng-Chung Lee holds in an AI or semiconductor company tracked on Silicon Floor, from their SEC filings, broken down: the shares held and how, then any restricted shares, options or other rights declared.
MKS (MKSI)
John Tseng-Chung Lee holds 134,776 MKS shares (0.20% of the company), worth about $37.9M at the last price, according to the Form 4 of Aug 14, 2026.
- Shares held: 134,776 (0.20%), $37.9M — Held in their own name.
- Share units: 84,828 (0.13%), $23.8M — MKS promised them as pay: each unit becomes a share when it vests, if its conditions are met. No vote until then.
Declarations
- MKS (MKSI) — Form 4 of Aug 14, 2026 (President & CEO): open-market sale of 10,000 at $302.01; 134,776 shares after 0001049502-26-000113
- MKS (MKSI) — Form 4 of May 22, 2026 (President & CEO): open-market sale of 10,000 at $315.48; 144,696 shares after 0001049502-26-000088
- MKS (MKSI) — Form 4 of Feb 20, 2026 (President & CEO): open-market sale of 13,310 at $256.05; open-market sale of 12,812 at $256.93; 154,696 shares after 0001049502-26-000030
- MKS (MKSI) — Form 4 of Feb 17, 2026 (President & CEO): option exercise or conversion of 22,088; option exercise or conversion of 7,654; 184,696 shares after 0001049502-26-000016
- MKS (MKSI) — Form 4 of Feb 8, 2026 (President & CEO) 0001049502-26-000002
- MKS (MKSI) — Form 4 of Oct 31, 2025 (President & CEO): option exercise or conversion of 352; option exercise or conversion of 1,651; 147,270 shares after 0001049502-25-000035
- MKS (MKSI) — Form 4 of Feb 18, 2025 (President & CEO): option exercise or conversion of 14,041; option exercise or conversion of 6,735; 147,117 shares after 0001127602-25-005631
- MKS (MKSI) — Form 4 of Feb 10, 2025 (President & CEO) 0001127602-25-004210
- MKS (MKSI) — Form 4 of Dec 6, 2024 (President & CEO): option exercise or conversion of 2,010; option exercise or conversion of 984; 112,689 shares after 0001127602-24-028957
Sources: SEC Schedules 13D and 13G (stakes above 5%, which count everything a person votes or can acquire within 60 days) and Forms 3, 4 and 5 (the shares a director, officer or 10% owner holds, filed within two business days of each trade). Values at the last price.