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Mks Inc (NASDAQ:MKSI)
US · Delayed Price · Currency is USD
Technology · Hardware, Equipment & Parts
204.07+7.53 (+3.83%)
Insider Score
––Not scored
MKSI Insider Score
Insiders filed in the last 90 days, but none of those trades qualified for scoring — round-trip buys and filings whose price is far off the market are excluded.
MKSI Stock Insider Trading Activity
MKSI stock’s insider trading shows 25 sales on the open market for an estimated $24.11M by company insiders over the last 6 months.
Not enough price history.
Insider Trading Activity (Form 4 Filings)
An insider trade occurs when an individual that has non-public information about a company buys or sells shares of that company’s stock. Examples of insiders include a company’s executive officers (CEO, CFO, COO), its board of directors, and its major shareholders. Insiders are required to submit their trading activity to the SEC through Form 4 filings.
Scored window · last 90 days0 qualifying buys0 insiders$0 bought— these are the numbers in the rankings table; the full history below shows every filing (buys, sells and older activity).
| Insider | Action | Shares | Avg Cost | Total | Δ Holdings | Held After | Date | Grade | Form 4 |
|---|---|---|---|---|---|---|---|---|---|
| Mora Elizabeth Director | Sell | 300 | $250.96 | $75.29K | 1.6% | 18,845 | Sep 1, 2026 | — | Form 4 |
| Lee John Tseng-Chung CEO | Sell | 10,000 | $302.01 | $3.02M | 6.9% | 134,776 | Aug 14, 2026 | — | Form 4 |
| Williams John Edward Other | Sell | 457 | $288.31 | $131.76K | 10.0% | 4,098 | Aug 3, 2026 | — | Form 4 |
| Schreiner James Alan COO | Sell | 812 | $346.41 | $281.28K | 4.0% | 19,418 | Jun 12, 2026 | — | Form 4 |
| Schreiner James Alan COO | Sell | 2,471 | $345.52 | $853.78K | 10.9% | 20,230 | Jun 12, 2026 | — | Form 4 |
| Schreiner James Alan COO | Sell | 217 | $347.00 | $75.30K | 1.1% | 19,201 | Jun 12, 2026 | — | Form 4 |
| Schreiner James Alan COO | Sell | 781 | $317.42 | $247.91K | 3.3% | 22,701 | Jun 10, 2026 | — | Form 4 |
| McCarthy Michelle M Other | Sell | 2,434 | $315.23 | $767.27K | 99.9% | 2 | Jun 5, 2026 | — | Form 4 |
| Henry David Philip Other | Sell | 6,000 | $314.43 | $1.89M | 36.5% | 10,422 | Jun 1, 2026 | — | Form 4 |
| Mora Elizabeth Director | Sell | 300 | $318.02 | $95.41K | 1.5% | 19,145 | Jun 1, 2026 | — | Form 4 |
| Donahue Joseph B Director | Sell | 2,100 | $327.95 | $688.70K | 17.3% | 10,033 | May 27, 2026 | — | Form 4 |
| COLELLA GERALD G Director | Sell | 464 | $330.38 | $153.30K | 1.2% | 39,553 | May 27, 2026 | — | Form 4 |
| COLELLA GERALD G Director | Sell | 8,210 | $331.45 | $2.72M | 20.8% | 31,343 | May 27, 2026 | — | Form 4 |
| COLELLA GERALD G Director | Sell | 4,876 | $332.04 | $1.62M | 15.6% | 26,467 | May 27, 2026 | — | Form 4 |
| COLELLA GERALD G Director | Sell | 1,811 | $335.46 | $607.52K | 6.8% | 24,656 | May 27, 2026 | — | Form 4 |
| COLELLA GERALD G Director | Sell | 1,626 | $336.54 | $547.21K | 6.6% | 23,030 | May 27, 2026 | — | Form 4 |
| COLELLA GERALD G Director | Sell | 213 | $337.05 | $71.79K | 0.9% | 22,817 | May 27, 2026 | — | Form 4 |
| COLELLA GERALD G Director | Sell | 2,800 | $338.58 | $948.02K | 12.3% | 20,017 | May 27, 2026 | — | Form 4 |
| Henry David Philip Other | Sell | 2,500 | $330.50 | $826.25K | 13.3% | 16,341 | May 26, 2026 | — | Form 4 |
| Mayampurath Ramakumar CFO | Sell | 8,810 | $315.48 | $2.78M | 100.0% | 1 | May 22, 2026 | — | Form 4 |
| Lee John Tseng-Chung CEO | Sell | 10,000 | $315.48 | $3.15M | 6.5% | 144,696 | May 22, 2026 | — | Form 4 |
| CANNONE PETER III Director | Sell | 1,350 | $303.40 | $409.59K | 14.8% | 7,794 | May 18, 2026 | — | Form 4 |
| Moloney Jacqueline F Director | Sell | 1,000 | $312.20 | $312.20K | 10.2% | 8,775 | May 14, 2026 | — | Form 4 |
| Moloney Jacqueline F Director | Sell | 1,400 | $318.99 | $446.59K | 12.5% | 9,775 | May 13, 2026 | — | Form 4 |
| Moloney Jacqueline F Director | Award | 782 | — | — | 7.5% | 11,175 | May 11, 2026 | — | Form 4 |
| JABRE WISSAM G Director | Award | 782 | — | — | 17.4% | 5,270 | May 11, 2026 | — | Form 4 |
| Mora Elizabeth Director | Award | 782 | — | — | 4.2% | 19,445 | May 11, 2026 | — | Form 4 |
| Burke Kathleen Flaherty Other | Sell | 4,355 | $319.94 | $1.39M | 8.1% | 49,439 | May 11, 2026 | — | Form 4 |
What these mean— the action is the SEC’s own Form 4 transaction code. Only a buy or a sell is an open-market trade; the rest are transfers, awards and exercises, which is why they carry no price.
- Sell (S) — Open-market or private sale
- Award (A) — Grant or award from the company, not a purchase
Disclaimer — Informational only — not investment advice. Insider transaction data is sourced from SEC Form 4 filings; market data from public feeds and may be delayed. The Insider Score is a proprietary score for research purposes and does not predict future performance. Always do your own research.