Nasdaq · CIK 0001049502
MKSI MKS INSTRUMENTS INC
Insider trading from SEC Form 4. Last filing 40 d ago. Close $264.50 on Oct 9, 2026, +119% from the 52-week low and -40% from the high.
Last 90 days
Net insider value
-$75k
more sold than bought
Buys
0
$0 by 0 insiders
Sells
1
$75k by 1 insider
Insiders on file
13
with a Form 4 at this company
Price and insider trades, last year
MKSIOct 9, 2026 · close 264.50
Daily candles, adjusted for splits and dividends. Green arrows are insider buys, red are sells, sized by value. Click a marked bar to open the signal.Charts by TradingView Lightweight Charts™
Signals
Open-market buys and sells at MKS INSTRUMENTS INC, scored.
| Score | Insider | Value | Holdings | Price context | Filed |
|---|---|---|---|---|---|
| 3Weak | Elizabeth Mora director sell | $75k 300 shares | -2% | - | |
| 0Weak | Elizabeth Mora director sell | $25k 300 shares | -2% | +41% from low-32% from high | |
| 43Moderate | Gerard G Colella director sell | $836k 8,000 shares | -12% | - | |
| 9Weak | Jacqueline F Moloney director sell | $34k 300 shares | -3% | - | |
| 8Weak | Elizabeth Mora director sell | $31k 275 shares | -2% | - |
Congressional trades
4 trades in MKSI disclosed by members of Congress under the STOCK Act. All congressional trades.
- Lisa C. McClainHouse · R-MI · last Nov 21, 20252 bought
2 sold
| Member | Trade | Asset | Reported range | Trade / filing date | Source |
|---|---|---|---|---|---|
Lisa C. McClain House · R-MI | Sale | MKSI MKS Inc. - Common Stock | $1,001 to $15k | Oct 30, 2025 / Nov 21, 2025 22 days after the trade | Clerk |
Lisa C. McClain House · R-MI | Purchase | MKSI MKS Inc. - Common Stock | $1,001 to $15k | Oct 30, 2025 / Nov 21, 2025 22 days after the trade | Clerk |
Lisa C. McClain House · R-MI | Sale | MKSI MKS Inc. - Common Stock | $1,001 to $15k | Oct 31, 2025 / Nov 21, 2025 21 days after the trade | Clerk |
Lisa C. McClain House · R-MI | Purchase | MKSI MKS Inc. - Common Stock | $1,001 to $15k | Aug 4, 2025 / Sep 12, 2025 39 days after the trade | Clerk |
Transactions
The last 58 rows filed, every code.
| Date | Insider | Transaction | Shares | Price | Value | Holdings after | Filed |
|---|---|---|---|---|---|---|---|
| Sep 1, 2026 | Elizabeth Mora director | SOpen-market sale Common Stock10b5-1 | -300 | $250.96 | $75k | 18,845 | 40 d ago |
| Jun 2, 2025 | Elizabeth Mora director | SOpen-market sale Common Stock10b5-1 | -300 | $81.78 | $25k | 19,563 | Jun 3, 2025 |
| May 12, 2025 | Peter Cannone III director | AGrant or award Common Stock | +2,479 | - | - | 9,612 | May 13, 2025 |
| May 12, 2025 | Gerard G Colella director | AGrant or award Common Stock | +2,479 | - | - | 8,217 | May 13, 2025 |
| May 12, 2025 | Joseph B Donahue director | AGrant or award Common Stock | +2,479 | - | - | 11,351 | May 13, 2025 |
| May 12, 2025 | Wissam G Jabre director | AGrant or award Common Stock | +2,479 | - | - | 4,488 | May 13, 2025 |
| May 12, 2025 | Jacqueline F Moloney director | AGrant or award Common Stock | +2,479 | - | - | 12,162 | May 13, 2025 |
| May 12, 2025 | Elizabeth Mora director | AGrant or award Common Stock | +2,479 | - | - | 19,863 | May 13, 2025 |
| May 12, 2025 | Raj Batra director | AGrant or award Common Stock | +2,479 | - | - | 15,445 | May 13, 2025 |
| Apr 17, 2025 | John Edward Williams EVP & GM, PSD | MOption exercise Common Stock | +1,740 | - | - | 3,566 | Apr 18, 2025 |
| Apr 17, 2025 | John Edward Williams EVP & GM, PSD | FTax withholding Common Stock | -565 | $63.69 | $36k | 3,001 | Apr 18, 2025 |
| Apr 17, 2025 | John Edward Williams EVP & GM, PSD | MOption exercise Restricted Stock Unitderivative | -1,740 | - | - | 8,291 | Apr 18, 2025 |
| Apr 15, 2025 | Michelle M McCarthy VP & Chief Accounting Officer | MOption exercise Common Stock | +968 | - | - | 968 | Apr 17, 2025 |
| Apr 15, 2025 | Michelle M McCarthy VP & Chief Accounting Officer | MOption exercise Common Stock | +1,106 | - | - | 2,074 | Apr 17, 2025 |
| Apr 15, 2025 | Michelle M McCarthy VP & Chief Accounting Officer | FTax withholding Common Stock | -608 | $68.48 | $42k | 1,466 | Apr 17, 2025 |
| Apr 15, 2025 | Michelle M McCarthy VP & Chief Accounting Officer | MOption exercise Restricted Stock Unitderivative | -968 | - | - | 5,422 | Apr 17, 2025 |
| Apr 15, 2025 | Michelle M McCarthy VP & Chief Accounting Officer | MOption exercise Restricted Stock Unitderivative | -1,106 | - | - | 4,316 | Apr 17, 2025 |
| Apr 15, 2025 | Michelle M McCarthy VP & Chief Accounting Officer | AGrant or award Restricted Stock Unitderivative | +5,210 | - | - | 9,526 | Apr 17, 2025 |
| Feb 18, 2025 | Kathleen Flaherty Burke EVP, GC & Secretary | MOption exercise Common Stock | +2,287 | - | - | 45,533 | Feb 19, 2025 |
| Feb 18, 2025 | David Philip Henry EVP, Operations & Corp Mktg | MOption exercise Common Stock | +1,528 | - | - | 18,306 | Feb 19, 2025 |
| Feb 18, 2025 | Gerard G Colella director | SOpen-market sale Common Stockindirect: By The Gerald G. Colella 2019 Trust | -8,000 | $104.53 | $836k | 60,017 | Feb 19, 2025 |
| Feb 18, 2025 | Kathleen Flaherty Burke EVP, GC & Secretary | MOption exercise Common Stock | +1,645 | - | - | 47,178 | Feb 19, 2025 |
| Feb 18, 2025 | David Philip Henry EVP, Operations & Corp Mktg | MOption exercise Common Stock | +1,099 | - | - | 19,405 | Feb 19, 2025 |
| Feb 18, 2025 | Kathleen Flaherty Burke EVP, GC & Secretary | MOption exercise Common Stock | +3,608 | - | - | 50,786 | Feb 19, 2025 |
| Feb 18, 2025 | David Philip Henry EVP, Operations & Corp Mktg | MOption exercise Common Stock | +2,406 | - | - | 21,811 | Feb 19, 2025 |
| Feb 18, 2025 | David Philip Henry EVP, Operations & Corp Mktg | MOption exercise Common Stock | +1,246 | - | - | 23,057 | Feb 19, 2025 |
| Feb 18, 2025 | Kathleen Flaherty Burke EVP, GC & Secretary | MOption exercise Common Stock | +1,870 | - | - | 52,656 | Feb 19, 2025 |
| Feb 18, 2025 | Kathleen Flaherty Burke EVP, GC & Secretary | MOption exercise Common Stock | +588 | - | - | 53,244 | Feb 19, 2025 |
| Feb 18, 2025 | David Philip Henry EVP, Operations & Corp Mktg | MOption exercise Common Stock | +456 | - | - | 23,513 | Feb 19, 2025 |
| Feb 18, 2025 | Kathleen Flaherty Burke EVP, GC & Secretary | MOption exercise Common Stock | +1,648 | - | - | 54,892 | Feb 19, 2025 |
| Feb 18, 2025 | David Philip Henry EVP, Operations & Corp Mktg | MOption exercise Common Stock | +1,278 | - | - | 24,791 | Feb 19, 2025 |
| Feb 18, 2025 | Kathleen Flaherty Burke EVP, GC & Secretary | FTax withholding Common Stock | -3,970 | $103.67 | $412k | 50,922 | Feb 19, 2025 |
| Feb 18, 2025 | David Philip Henry EVP, Operations & Corp Mktg | FTax withholding Common Stock | -2,372 | $103.67 | $246k | 22,419 | Feb 19, 2025 |
| Feb 18, 2025 | Kathleen Flaherty Burke EVP, GC & Secretary | AGrant or award Restricted Stock Unitderivative | +7,822 | - | - | 29,422 | Feb 19, 2025 |
| Feb 18, 2025 | David Philip Henry EVP, Operations & Corp Mktg | AGrant or award Restricted Stock Unitderivative | +6,163 | - | - | 21,300 | Feb 19, 2025 |
| Feb 18, 2025 | Kathleen Flaherty Burke EVP, GC & Secretary | MOption exercise Restricted Stock Unitderivative | -2,287 | - | - | 27,135 | Feb 19, 2025 |
| Feb 18, 2025 | David Philip Henry EVP, Operations & Corp Mktg | MOption exercise Restricted Stock Unitderivative | -1,528 | - | - | 19,771 | Feb 19, 2025 |
| Feb 18, 2025 | Kathleen Flaherty Burke EVP, GC & Secretary | MOption exercise Restricted Stock Unitderivative | -1,645 | - | - | 25,490 | Feb 19, 2025 |
| Feb 18, 2025 | David Philip Henry EVP, Operations & Corp Mktg | MOption exercise Restricted Stock Unitderivative | -1,099 | - | - | 18,672 | Feb 19, 2025 |
| Feb 18, 2025 | Kathleen Flaherty Burke EVP, GC & Secretary | MOption exercise Restricted Stock Unitderivative | -3,608 | - | - | 21,882 | Feb 19, 2025 |
| Feb 18, 2025 | David Philip Henry EVP, Operations & Corp Mktg | MOption exercise Restricted Stock Unitderivative | -2,406 | - | - | 16,266 | Feb 19, 2025 |
| Feb 18, 2025 | David Philip Henry EVP, Operations & Corp Mktg | MOption exercise Restricted Stock Unitderivative | -1,246 | - | - | 15,020 | Feb 19, 2025 |
| Feb 18, 2025 | Kathleen Flaherty Burke EVP, GC & Secretary | MOption exercise Restricted Stock Unitderivative | -1,870 | - | - | 20,012 | Feb 19, 2025 |
| Feb 18, 2025 | Kathleen Flaherty Burke EVP, GC & Secretary | MOption exercise Restricted Stock Unitderivative | -588 | - | - | 19,424 | Feb 19, 2025 |
| Feb 18, 2025 | David Philip Henry EVP, Operations & Corp Mktg | MOption exercise Restricted Stock Unitderivative | -456 | - | - | 14,564 | Feb 19, 2025 |
| Feb 18, 2025 | Kathleen Flaherty Burke EVP, GC & Secretary | MOption exercise Restricted Stock Unitderivative | -1,648 | - | - | 17,776 | Feb 19, 2025 |
| Feb 18, 2025 | David Philip Henry EVP, Operations & Corp Mktg | MOption exercise Restricted Stock Unitderivative | -1,278 | - | - | 13,286 | Feb 19, 2025 |
| Feb 10, 2025 | Kathleen Flaherty Burke EVP, GC & Secretary | AGrant or award Restricted Stock Unitderivative | +1,766 | - | - | 21,599 | Feb 11, 2025 |
| Feb 10, 2025 | David Philip Henry EVP, Operations & Corp Mktg | AGrant or award Restricted Stock Unitderivative | +1,369 | - | - | 15,137 | Feb 11, 2025 |
| Dec 10, 2024 | Jacqueline F Moloney director | SOpen-market sale Common Stock10b5-1 | -300 | $114.80 | $34k | 9,983 | Dec 11, 2024 |
| Dec 6, 2024 | John Tseng-Chung Lee President & CEO | MOption exercise Common Stock | +2,010 | - | - | 114,699 | Dec 10, 2024 |
| Dec 6, 2024 | John Tseng-Chung Lee President & CEO | MOption exercise Common Stock | +984 | - | - | 115,683 | Dec 10, 2024 |
| Dec 6, 2024 | John Tseng-Chung Lee President & CEO | FTax withholding Common Stock | -2,994 | $114.60 | $343k | 112,689 | Dec 10, 2024 |
| Dec 6, 2024 | John Tseng-Chung Lee President & CEO | MOption exercise Restricted Stock Unitderivative | -2,010 | - | - | 102,868 | Dec 10, 2024 |
| Dec 6, 2024 | John Tseng-Chung Lee President & CEO | MOption exercise Restricted Stock Unitderivative | -984 | - | - | 101,884 | Dec 10, 2024 |
| Dec 2, 2024 | Elizabeth Mora director | SOpen-market sale Common Stock10b5-1 | -275 | $113.41 | $31k | 17,659 | Dec 3, 2024 |
| Nov 15, 2024 | Ramakumar Mayampurath EVP, CFO & Treasurer | AGrant or award Restricted Stock Unitderivative | +16,591 | - | - | 16,591 | Nov 18, 2024 |
| Nov 4, 2024 | Wissam G Jabre director | AGrant or award Common Stock | +2,009 | - | - | 2,009 | Nov 5, 2024 |
Insiders
Everyone who has filed a Form 4 here.
- Raj Batradirector
- Kathleen Flaherty BurkeEVP, GC & Secretary
- Peter Cannone IIIdirector
- Gerard G Colelladirector
- Joseph B Donahuedirector
- David Philip HenryEVP, Operations & Corp Mktg
- Wissam G Jabredirector, cfo, officer
- John Tseng-Chung LeePresident & CEO
- Ramakumar MayampurathEVP, CFO & Treasurer
- Michelle M McCarthyVP & Chief Accounting Officer
- Jacqueline F Moloneydirector
- Elizabeth Moradirector
- John Edward WilliamsEVP & GM, PSD
Not investment advice. Scores and forward returns are decision support built from public SEC filings and past prices; they describe what happened after comparable filings, not what will happen after this one. Do your own research and size your risk.