MKSI Insider Trading

Insider Ownership Percentage: 0.57%
Insider Buying (Last 12 Months): $0.00
Insider Selling (Last 12 Months): $38,695,637.88

MKS Insider Trading History Chart

This chart shows the insider buying and selling history at MKS by year and by quarter.

Skip ChartChart Data in Insider Trading History Table

MKS Share Price & Price History

Current Price: $240.23
Price Change: Price Increase of +4.95 (2.10%)
As of 09/17/2026 04:00 PM ET

This chart shows the closing price history over time for MKSI up to the past year.

Skip Chart and Table DataPrice Data in Insider Trading History Table
Days: 30 | 90 | 365

MKS Insider Trading History

Transaction DateInsider NameTitleBuy/SellNumber of SharesAverage Share PriceTotal TransactionShares Held After TransactionDetails
9/1/2026Elizabeth MoraDirectorSell300$250.96$75,288.0018,845View SEC Filing Icon  
8/14/2026John Tseng-Chung LeeCEOSell10,000$302.01$3,020,100.00134,776View SEC Filing Icon  
8/3/2026John Edward WilliamsEVPSell457$288.31$131,757.674,098View SEC Filing Icon  
6/5/2026Michelle M MccarthyCAOSell2,434$315.23$767,269.822View SEC Filing Icon  
5/27/2026Gerald G ColellaDirectorSell20,000$333.40$6,668,000.0020,017View SEC Filing Icon  
5/27/2026Joseph B DonahueDirectorSell2,100$327.95$688,695.0010,033View SEC Filing Icon  
5/26/2026David Philip HenryEVPSell2,500$330.50$826,250.0016,341View SEC Filing Icon  
5/22/2026John Tseng-Chung LeeCEOSell10,000$315.48$3,154,800.00144,696View SEC Filing Icon  
5/22/2026Ramakumar MayampurathCFOSell8,810$315.48$2,779,378.801View SEC Filing Icon  
5/18/2026Peter J. Cannone, IIIDirectorSell1,350$303.40$409,590.007,794View SEC Filing Icon  
5/14/2026Jacqueline F. MoloneyDirectorSell1,000$312.20$312,200.008,775View SEC Filing Icon  
5/13/2026Jacqueline F. MoloneyDirectorSell1,400$318.99$446,586.009,775View SEC Filing Icon  
5/11/2026Kathleen Flaherty BurkeEVPSell4,355$319.94$1,393,338.7049,439View SEC Filing Icon  
3/12/2026Jacqueline F. MoloneyDirectorSell340$213.77$72,681.8010,393View SEC Filing Icon  
3/6/2026Eric Robert TarantoEVPSell4,568$220.52$1,007,335.3615,445View SEC Filing Icon  
3/2/2026Elizabeth MoraDirectorSell300$239.44$71,832.0018,663View SEC Filing Icon  
2/24/2026Gerald G ColellaDirectorSell10,000$253.97$2,539,700.0040,017View SEC Filing Icon  
2/20/2026David Philip HenryEVPSell2,000$261.56$523,120.0018,841View SEC Filing Icon  
2/20/2026Eric Robert TarantoEVPSell1,453$247.55$359,690.1520,013View SEC Filing Icon  
2/20/2026Gerald G ColellaDirectorSell10,000$252.90$2,529,000.0050,017View SEC Filing Icon  
2/20/2026Jacqueline F. MoloneyDirectorSell829$247.55$205,218.9510,733View SEC Filing Icon  
2/20/2026John Edward WilliamsEVPSell2,043$256.41$523,845.633,640View SEC Filing Icon  
2/20/2026John Tseng-Chung LeeCEOSell30,000$256.77$7,703,100.00154,696View SEC Filing Icon  
2/20/2026Kathleen Flaherty BurkeEVPSell4,254$250.00$1,063,500.0053,794View SEC Filing Icon  
2/20/2026Michelle M MccarthyCAOSell1,466$250.00$366,500.00View SEC Filing Icon  
2/20/2026Peter J. Cannone, IIIDirectorSell1,250$258.06$322,575.008,362View SEC Filing Icon  
12/2/2025Elizabeth MoraDirectorSell300$158.81$47,643.0018,963View SEC Filing Icon  
10/1/2025Jacqueline F. MoloneyDirectorSell300$122.14$36,642.0011,562View SEC Filing Icon  
9/18/2025David Philip HenryEVPSell5,000$130.00$650,000.0015,571View SEC Filing Icon  
9/2/2025Elizabeth MoraDirectorSell300$99.85$29,955.0019,263View SEC Filing Icon  
8/1/2025Jacqueline F. MoloneyDirectorSell300$92.10$27,630.0011,862View SEC Filing Icon  
7/3/2025David Philip HenryEVPSell2,000$105.00$210,000.0020,571View SEC Filing Icon  
3/3/2025Elizabeth MoraDirectorSell275$92.46$25,426.5017,384View SEC Filing Icon  
2/18/2025Gerard G. ColellaDirectorSell8,000$104.53$836,240.0060,017View SEC Filing Icon  
12/10/2024Jacqueline F. MoloneyDirectorSell300$114.80$34,440.009,983View SEC Filing Icon  
12/2/2024Elizabeth MoraDirectorSell275$113.41$31,187.7517,659View SEC Filing Icon  
10/1/2024Jacqueline F. MoloneyDirectorSell250$108.90$27,225.0010,283View SEC Filing Icon  
9/3/2024Elizabeth MoraDirectorSell275$115.97$31,891.7517,934View SEC Filing Icon  
8/16/2024John Edward WilliamsEVPSell1,800$118.71$213,678.0013View SEC Filing Icon  
8/1/2024Jacqueline F. MoloneyDirectorSell250$123.46$30,865.0010,533View SEC Filing Icon  
6/3/2024Elizabeth MoraDirectorSell275$129.41$35,587.7518,209View SEC Filing Icon  
4/1/2024Elizabeth MoraDirectorSell250$133.00$33,250.0016,862View SEC Filing Icon  
3/1/2024Jacqueline F. MoloneyDirectorSell250$122.89$30,722.509,161View SEC Filing Icon  
3/1/2024Kathleen Flaherty BurkeEVPSell7,411$122.89$910,737.7942,999View SEC Filing Icon  
2/22/2024Seth H. BagshawCFOSell32,865$123.28$4,051,597.201View SEC Filing Icon  
2/9/2024Gerard G. ColellaDirectorSell10,000$120.00$1,200,000.0068,017View SEC Filing Icon  
1/22/2024Gerard G. ColellaDirectorSell10,000$110.00$1,100,000.0078,017View SEC Filing Icon  
1/2/2024Elizabeth MoraDirectorSell250$100.90$25,225.0017,112View SEC Filing Icon  
12/1/2023Jacqueline F. MoloneyDirectorSell250$82.23$20,557.5011,328View SEC Filing Icon  
11/7/2023David Philip HenryEVPBuy2,500$68.34$170,850.0011,073View SEC Filing Icon  
10/2/2023Elizabeth MoraDirectorSell250$87.15$21,787.5017,362View SEC Filing Icon  
See Full Table

SEC Filings (Institutional Ownership Changes) for MKS (NASDAQ:MKSI)

99.79% of MKS stock is owned by institutions. Institutional ownership can be a sign of analyst confidence in the fundamentals of the stock.

Institutional Buying and Selling by Quarter

This chart shows the instiutional buying and selling at MKSI by year and by quarter.

Skip Institutional Buying and Selling Chart and Table DataRead Chart Data in Institutional Trading History Table

MKS Institutional Trading History

Reporting DateHedge FundShares HeldMarket Value% of PortfolioQuarterly Change in SharesOwnership in CompanyDetails
9/15/2026Reynders McVeigh Capital Management LLC513$0.23M0.0%N/A0.001%Search for SEC Filing on Google Icon
9/9/2026Sequoia Financial Advisors LLC1,961$0.87M0.0%+35.7%0.003%Search for SEC Filing on Google Icon
9/9/2026Tidal Investments LLC44,846$19.95M0.0%+42.2%0.066%Search for SEC Filing on Google Icon
9/9/2026Arlington Capital Management Inc.856$0.38M0.2%N/A0.001%Search for SEC Filing on Google Icon
9/9/2026BlueCrest Capital Management Ltd19,705$8.77M0.3%+11.8%0.029%Search for SEC Filing on Google Icon
9/9/2026WINTON GROUP Ltd6,203$2.76M0.1%+287.7%0.009%Search for SEC Filing on Google Icon
9/9/2026Engineers Gate Manager LP4,399$1.96M0.0%-77.8%0.007%Search for SEC Filing on Google Icon
9/9/2026Pinnacle Wealth Management Advisory Group LLC792$0.35M0.0%N/A0.001%Search for SEC Filing on Google Icon
9/9/2026Integrated Wealth Concepts LLC2,195$0.98M0.0%+6.9%0.003%Search for SEC Filing on Google Icon
9/9/2026NewEdge Advisors LLC6,724$2.99M0.0%-72.6%0.010%Search for SEC Filing on Google Icon
9/9/2026IFP Advisors Inc434$0.19M0.0%+129.6%0.001%Search for SEC Filing on Google Icon
9/9/2026Baird Financial Group Inc.2,252$1M0.0%+2.9%0.003%Search for SEC Filing on Google Icon
9/8/2026Allworth Financial LP1,402$0.62M0.0%+24.3%0.002%Search for SEC Filing on Google Icon
9/8/2026Arizona State Retirement System18,576$8.26M0.0%+0.7%0.027%Search for SEC Filing on Google Icon
9/8/2026West Family Investments Inc.482$0.21M0.1%N/A0.001%Search for SEC Filing on Google Icon
9/8/2026Waverly Advisors LLC846$0.38M0.0%N/A0.001%Search for SEC Filing on Google Icon
9/8/2026Nykredit A S2,289$1.02M0.0%N/A0.003%Search for SEC Filing on Google Icon
9/4/2026Parkside Financial Bank & Trust133$59K0.0%-26.5%0.000%Search for SEC Filing on Google Icon
9/2/2026Allianz Asset Management GmbH34,970$15.56M0.0%N/A0.052%Search for SEC Filing on Google Icon
8/27/2026Corient Private Wealth LP36,160$16.08M0.0%+0.8%0.053%Search for SEC Filing on Google Icon
8/26/2026HighTower Advisors LLC5,565$2.48M0.0%-55.1%0.008%Search for SEC Filing on Google Icon
8/25/2026VIRGINIA RETIREMENT SYSTEMS ET Al22,900$10.19M0.1%N/A0.034%Search for SEC Filing on Google Icon
8/23/2026Wedmont Private Capital4,098$1.82M0.0%+6.2%0.006%Search for SEC Filing on Google Icon
8/23/2026HB Wealth Management LLC2,752$1.22M0.0%+35.3%0.004%Search for SEC Filing on Google Icon
8/23/2026Angeles Wealth Management LLC917$0.41M0.0%+4.8%0.001%Search for SEC Filing on Google Icon
8/22/2026AlphaGrep UK Ltd862$0.38M0.1%N/A0.001%Search for SEC Filing on Google Icon
8/22/2026Oakmont Investment Advisors Inc.500$0.22M0.2%N/A0.001%Search for SEC Filing on Google Icon
8/22/2026Syon Capital LLC2,901$1.29M0.1%-12.7%0.004%Search for SEC Filing on Google Icon
8/22/2026Concurrent Investment Advisors LLC939$0.42M0.0%N/A0.001%Search for SEC Filing on Google Icon
8/21/2026AXQ Capital LP3,294$1.47M0.2%-54.6%0.005%Search for SEC Filing on Google Icon
8/21/2026Retireful LLC3,342$1.49M1.4%N/A0.005%Search for SEC Filing on Google Icon
8/21/2026Greenspring Advisors LLC483$0.22M0.0%N/A0.001%Search for SEC Filing on Google Icon
8/21/2026Nykredit A S2,289$1.02M0.0%N/A0.003%Search for SEC Filing on Google Icon
8/20/2026Proficio Capital Partners LLC1,054$0.47M0.0%N/A0.002%Search for SEC Filing on Google Icon
8/20/2026Spyglass Capital Management LLC118,526$52.72M2.9%N/A0.175%Search for SEC Filing on Google Icon
8/20/2026Teza Capital Management LLC1,084$0.48M0.9%N/A0.002%Search for SEC Filing on Google Icon
8/20/2026BTG Pactual Asset Management US LLC532$0.24M0.0%N/A0.001%Search for SEC Filing on Google Icon
8/20/2026Senator Investment Group LP65,000$28.91M1.1%N/A0.096%Search for SEC Filing on Google Icon
8/20/2026Sigma Planning Corp1,706$0.76M0.0%N/A0.003%Search for SEC Filing on Google Icon
8/20/2026Benjamin Edwards Inc.1,118$0.50M0.0%-3.7%0.002%Search for SEC Filing on Google Icon
8/20/2026Flputnam Investment Management Co.485$0.22M0.0%N/A0.001%Search for SEC Filing on Google Icon
8/20/2026Northwestern Mutual Wealth Management Co.173,207$77.04M0.0%+76,880.9%0.256%Search for SEC Filing on Google Icon
8/19/2026Hsbc Holdings PLC56,935$24.98M0.0%+2,274.3%0.084%Search for SEC Filing on Google Icon
8/19/2026Archer Investment Corp4,545$2.02M0.3%N/A0.007%Search for SEC Filing on Google Icon
8/18/2026Empowered Funds LLC3,714$1.65M0.0%N/A0.005%Search for SEC Filing on Google Icon
8/18/2026United Capital Financial Advisors LLC2,866$1.28M0.0%N/A0.004%Search for SEC Filing on Google Icon
8/18/2026Jefferies Financial Group Inc.1,023$0.46M0.0%N/A0.002%Search for SEC Filing on Google Icon
8/18/2026Public Employees Retirement System of Ohio38,346$17.06M0.1%N/A0.057%Search for SEC Filing on Google Icon
8/17/2026Capstone Investment Advisors LLC628$0.28M0.0%N/A0.001%Search for SEC Filing on Google Icon
8/17/2026Proficio Capital Partners LLC1,054$0.47M0.0%N/A0.002%Search for SEC Filing on Google Icon
8/17/2026Stonebridge Capital Management Inc.1,000$0.45M0.2%N/A0.001%Search for SEC Filing on Google Icon
8/17/2026Pure Financial Advisors LLC754$0.34M0.0%N/A0.001%Search for SEC Filing on Google Icon
8/17/2026Transamerica Financial Advisors LLC89$40K0.0%N/A0.000%Search for SEC Filing on Google Icon
8/17/2026Corient Private Wealth LP34,868$15.51M0.0%N/A0.052%Search for SEC Filing on Google Icon
8/17/2026Park West Asset Management LLC138,740$61.71M4.2%N/A0.205%Search for SEC Filing on Google Icon
8/17/2026Bank of America Corp DE520,847$231.67M0.0%N/A0.770%Search for SEC Filing on Google Icon
8/15/2026Strategic Global Advisors LLC13,030$5.80M0.8%N/A0.019%Search for SEC Filing on Google Icon
8/15/2026Light Street Capital Management LLC103,800$46.17M5.2%-15.1%0.154%Search for SEC Filing on Google Icon
8/15/2026First Bancorp Inc ME161$72K0.0%N/A0.000%Search for SEC Filing on Google Icon
8/15/2026Jupiter Topco LLC29,470$13.11M0.0%N/A0.044%Search for SEC Filing on Google Icon
8/14/2026Hsbc Holdings PLC56,935$24.98M0.0%N/A0.084%Search for SEC Filing on Google Icon
8/14/2026Ancora Advisors LLC82$36K0.0%N/A0.000%Search for SEC Filing on Google Icon
8/14/2026Expect Equity LLC10,655$4.74M3.0%N/A0.016%Search for SEC Filing on Google Icon
8/14/2026PDT Partners LLC72,347$32.18M1.7%N/A0.107%Search for SEC Filing on Google Icon
8/14/2026Canada Pension Plan Investment Board53,200$23.66M0.0%N/A0.079%Search for SEC Filing on Google Icon
8/14/2026Legal & General Group Plc117,817$51.82M0.0%N/A0.174%Search for SEC Filing on Google Icon
8/14/2026Jones Financial Companies Lllp158$70K0.0%N/A0.000%Search for SEC Filing on Google Icon
8/14/2026Cetera Trust Company N.A2,915$1.30M0.7%N/A0.004%Search for SEC Filing on Google Icon
8/14/2026Algert Global LLC45,270$20.14M0.2%+2.7%0.067%Search for SEC Filing on Google Icon
8/13/2026Infrastructure Capital Advisors LLC2,014$0.90M0.1%N/A0.003%Search for SEC Filing on Google Icon
8/13/2026Maxi Investments CY Ltd1,957$0.87M0.2%N/A0.003%Search for SEC Filing on Google Icon
8/13/2026Cibc World Market Inc.615$0.27M0.0%N/A0.001%Search for SEC Filing on Google Icon
8/13/2026OMERS ADMINISTRATION Corp1,200$0.53M0.0%N/A0.002%Search for SEC Filing on Google Icon
8/13/2026Sanctuary Advisors LLC7,897$3.51M0.0%N/A0.012%Search for SEC Filing on Google Icon
8/13/2026Wealth High Governance Capital Ltda27,600$12.28M3.7%N/A0.041%Search for SEC Filing on Google Icon
8/13/2026Meiji Yasuda Asset Management Co Ltd.1,563$0.70M0.0%N/A0.002%Search for SEC Filing on Google Icon
8/13/2026Globeflex Capital L P29,241$13.01M1.7%N/A0.043%Search for SEC Filing on Google Icon
8/12/2026Commerce Bank6,224$2.77M0.0%N/A0.009%Search for SEC Filing on Google Icon
8/12/2026Pinnbrook Capital Management LP12,700$5.65M0.6%N/A0.019%Search for SEC Filing on Google Icon
8/12/2026Northwestern Mutual Wealth Management Co.173,207$77.04M0.0%N/A0.256%Search for SEC Filing on Google Icon
8/12/2026Quantbot Technologies LP7,715$3.43M0.1%N/A0.011%Search for SEC Filing on Google Icon
8/12/2026Fourier Capital Management Ltd29,858$13.28M20.8%N/A0.044%Search for SEC Filing on Google Icon
8/12/2026Harber Asset Management LLC9,100$4.05M2.4%N/A0.013%Search for SEC Filing on Google Icon
8/12/2026Landscape Capital Management L.L.C.775$0.35M0.0%N/A0.001%Search for SEC Filing on Google Icon
8/12/2026EP Wealth Advisors LLC3,335$1.48M0.0%N/A0.005%Search for SEC Filing on Google Icon
8/12/2026Rakuten Securities Inc.89$40K0.0%N/A0.000%Search for SEC Filing on Google Icon
8/12/2026Ieq Capital LLC21,702$9.65M0.0%N/A0.032%Search for SEC Filing on Google Icon
8/12/2026Callan Family Office LLC4,093$1.82M0.0%N/A0.006%Search for SEC Filing on Google Icon
8/11/2026Keating Financial Advisory Services Inc.56$25K0.0%N/A0.000%Search for SEC Filing on Google Icon
8/11/2026Bowie Capital Management LLC42,649$18.97M0.8%N/A0.063%Search for SEC Filing on Google Icon
8/11/2026Allworth Financial LP1,402$0.62M0.0%N/A0.002%Search for SEC Filing on Google Icon
8/11/2026Greenspring Advisors LLC483$0.22M0.0%N/A0.001%Search for SEC Filing on Google Icon
8/11/2026NFJ Investment Group LLC36,697$16.32M0.6%N/A0.054%Search for SEC Filing on Google Icon
8/11/2026Ceredex Value Advisors LLC56,650$25.20M0.7%N/A0.084%Search for SEC Filing on Google Icon
8/11/2026MJP Associates Inc. ADV604$0.27M0.0%N/A0.001%Search for SEC Filing on Google Icon
8/11/2026Trillium Asset Management LLC11,334$5.04M0.2%N/A0.017%Search for SEC Filing on Google Icon
8/11/2026Value Holdings Management CO. LLC159,452$70.93M11.9%N/A0.236%Search for SEC Filing on Google Icon
8/11/2026Vise Technologies Inc.8,211$3.65M0.0%N/A0.012%Search for SEC Filing on Google Icon
8/11/2026OVERSEA CHINESE BANKING Corp Ltd18,477$8.22M0.2%N/A0.027%Search for SEC Filing on Google Icon
8/11/2026Madison Asset Management LLC316,694$140.87M1.7%N/A0.469%Search for SEC Filing on Google Icon
Data available starting January 2016

See Full Table
MKS logo
MKS Instruments, Inc. provides foundational technology solutions to semiconductor manufacturing, electronics and packaging, and specialty industrial applications in the United States, Germany, China, South Korea, and internationally. It operates through Vacuum Solutions Division (VSD), Photonics Solutions Division (PSD), and Material Solutions Division (MSD) segments. The VSD segment provides foundational technology solutions, including pressure measurement and control, flow measurement and control, gas and vapor delivery, gas composition analysis, electronic control technology, reactive gas generation and delivery, power generation and delivery, and vacuum technology. The PSD segment offers range of solutions, which include lasers, beam measurement and profiling, precision motion control, vibration isolation systems, photonics instruments, temperature sensing, opto-mechanical components, optical elements, systems for flexible PCB laser processing, and laser-based systems, as well as high density interconnect PCB and package manufacturing. The MSD segment develops, process, and manufactures technologies comprising advanced surface modification, electroless and electrolytic plating, and surface finishing for chemistry, equipment, software, and services markets, as well as high-technology applications. In addition, the company sells its products and services through direct sales, network of independent distributors, and sales representatives, as well as websites, including product catalogs. The company was incorporated in 1961 and is headquartered in Andover, Massachusetts.
Read More on MKS

Today's Range

Now: $240.23
Low: $238.45
High: $250.84

50 Day Range

MA: $292.27
Low: $231.50
High: $368.58

52 Week Range

Now: $240.23
Low: $119.62
High: $447.62

Volume

1,026,730 shs

Average Volume

1,222,831 shs

Market Capitalization

$16.24 billion

P/E Ratio

38.31

Dividend Yield

0.43%

Beta

1.98

Who are the company insiders with the largest holdings of MKS?

MKS's top insider investors include:
  1. Carlyle Partners Vi Cayman Hol (Major Shareholder)
  2. John Tseng-Chung Lee (CEO)
  3. Leo Berlinghieri (CEO)
  4. Gerard G Colella (Director)
  5. Gerard G Colella (CEO)
  6. Kathleen Flaherty Burke (EVP)
  7. Gerald G Colella (Director)
  8. Seth H Bagshaw (CFO)
  9. Seth H Bagshaw (CFO)
  10. Seth H Bagshaw (VP)
Learn More about top insider investors at MKS.

Who are the major institutional investors of MKS?

MKS's top institutional shareholders include:
  1. Bank of America Corp DE — 0.77%
  2. Madison Asset Management LLC — 0.47%
  3. TimesSquare Capital Management LLC — 0.43%
  4. Northwestern Mutual Wealth Management Co. — 0.26%
  5. Northwestern Mutual Wealth Management Co. — 0.26%
  6. Handelsbanken Fonder AB — 0.24%
Learn More about top institutional investors of MKS stock.

Which major investors are selling MKS stock?

During the last quarter, MKSI stock was sold by these institutional investors:
  1. Handelsbanken Fonder AB
  2. Light Street Capital Management LLC
  3. NewEdge Advisors LLC
  4. Engineers Gate Manager LP
  5. Assenagon Asset Management S.A.
  6. HighTower Advisors LLC
  7. AXQ Capital LP
  8. Avior Wealth Management LLC
Within the previous year, company insiders that have sold MKS company stock include:
  1. John Tseng-Chung Lee (CEO)
  2. Kathleen Flaherty Burke (EVP)
  3. Gerald G Colella (Director)
  4. Eric Robert Taranto (EVP)
  5. Elizabeth Mora (Director)
  6. David Philip Henry (EVP)
  7. Jacqueline F Moloney (Director)
  8. Joseph B Donahue (Director)
  9. Peter Cannone III (Director)
  10. John Edward Williams (EVP)
  11. Michelle M Mccarthy (CAO)
  12. Ramakumar Mayampurath (CFO)
Learn More investors selling MKS stock.

Which major investors are buying MKS stock?

In the previous quarter, MKSI stock was bought by institutional investors including:
  1. Bank of America Corp DE
  2. Madison Asset Management LLC
  3. TimesSquare Capital Management LLC
  4. Northwestern Mutual Wealth Management Co.
  5. Northwestern Mutual Wealth Management Co.
  6. Value Holdings Management CO. LLC
  7. Park West Asset Management LLC
  8. Spyglass Capital Management LLC