MKSI Insider Trading

Insider Trading Chart
Insider Trading History
Frequently Asked Questions
About

Insider Ownership Percentage: 0.57%

Insider Buying (Last 12 Months): $0.00

Insider Selling (Last 12 Months): $38,008,995.88

MKS Insider Trading History Chart

MKS Share Price & Price History

^$202.04

+0.30 (1.20%)

As of 10/30/2026 04:00 PM ET

Days: 30 | 90 | 365

MKS Insider Trading History

Transaction Date	Insider Name	Title	Buy/Sell	Number of Shares	Average Share Price	Total Transaction	Shares Held After Transaction
9/1/2026	Elizabeth Mora	Director	Sell	300	$250.96	$75,288.00	18,845
8/14/2026	John Tseng-Chung Lee	CEO	Sell	10,000	$302.01	$3,020,100.00	134,776
8/3/2026	John Edward Williams	EVP	Sell	457	$288.31	$131,757.67	4,098
6/5/2026	Michelle M Mccarthy	CAO	Sell	2,434	$315.23	$767,269.82	2
5/27/2026	Gerald G Colella	Director	Sell	20,000	$333.40	$6,668,000.00	20,017
5/27/2026	Joseph B Donahue	Director	Sell	2,100	$327.95	$688,695.00	10,033
5/26/2026	David Philip Henry	EVP	Sell	2,500	$330.50	$826,250.00	16,341
5/22/2026	John Tseng-Chung Lee	CEO	Sell	10,000	$315.48	$3,154,800.00	144,696
5/22/2026	Ramakumar Mayampurath	CFO	Sell	8,810	$315.48	$2,779,378.80	1
5/18/2026	Peter J. Cannone, III	Director	Sell	1,350	$303.40	$409,590.00	7,794
5/14/2026	Jacqueline F. Moloney	Director	Sell	1,000	$312.20	$312,200.00	8,775
5/13/2026	Jacqueline F. Moloney	Director	Sell	1,400	$318.99	$446,586.00	9,775
5/11/2026	Kathleen Flaherty Burke	EVP	Sell	4,355	$319.94	$1,393,338.70	49,439
3/12/2026	Jacqueline F. Moloney	Director	Sell	340	$213.77	$72,681.80	10,393
3/6/2026	Eric Robert Taranto	EVP	Sell	4,568	$220.52	$1,007,335.36	15,445
3/2/2026	Elizabeth Mora	Director	Sell	300	$239.44	$71,832.00	18,663
2/24/2026	Gerald G Colella	Director	Sell	10,000	$253.97	$2,539,700.00	40,017
2/20/2026	David Philip Henry	EVP	Sell	2,000	$261.56	$523,120.00	18,841
2/20/2026	Eric Robert Taranto	EVP	Sell	1,453	$247.55	$359,690.15	20,013
2/20/2026	Gerald G Colella	Director	Sell	10,000	$252.90	$2,529,000.00	50,017
2/20/2026	Jacqueline F. Moloney	Director	Sell	829	$247.55	$205,218.95	10,733
2/20/2026	John Edward Williams	EVP	Sell	2,043	$256.41	$523,845.63	3,640
2/20/2026	John Tseng-Chung Lee	CEO	Sell	30,000	$256.77	$7,703,100.00	154,696
2/20/2026	Kathleen Flaherty Burke	EVP	Sell	4,254	$250.00	$1,063,500.00	53,794
2/20/2026	Michelle M Mccarthy	CAO	Sell	1,466	$250.00	$366,500.00
2/20/2026	Peter J. Cannone, III	Director	Sell	1,250	$258.06	$322,575.00	8,362
12/2/2025	Elizabeth Mora	Director	Sell	300	$158.81	$47,643.00	18,963
10/1/2025	Jacqueline F. Moloney	Director	Sell	300	$122.14	$36,642.00	11,562
9/18/2025	David Philip Henry	EVP	Sell	5,000	$130.00	$650,000.00	15,571
9/2/2025	Elizabeth Mora	Director	Sell	300	$99.85	$29,955.00	19,263
8/1/2025	Jacqueline F. Moloney	Director	Sell	300	$92.10	$27,630.00	11,862
7/3/2025	David Philip Henry	EVP	Sell	2,000	$105.00	$210,000.00	20,571
3/3/2025	Elizabeth Mora	Director	Sell	275	$92.46	$25,426.50	17,384
2/18/2025	Gerard G. Colella	Director	Sell	8,000	$104.53	$836,240.00	60,017
12/10/2024	Jacqueline F. Moloney	Director	Sell	300	$114.80	$34,440.00	9,983
12/2/2024	Elizabeth Mora	Director	Sell	275	$113.41	$31,187.75	17,659
10/1/2024	Jacqueline F. Moloney	Director	Sell	250	$108.90	$27,225.00	10,283
9/3/2024	Elizabeth Mora	Director	Sell	275	$115.97	$31,891.75	17,934
8/16/2024	John Edward Williams	EVP	Sell	1,800	$118.71	$213,678.00	13
8/1/2024	Jacqueline F. Moloney	Director	Sell	250	$123.46	$30,865.00	10,533
6/3/2024	Elizabeth Mora	Director	Sell	275	$129.41	$35,587.75	18,209
4/1/2024	Elizabeth Mora	Director	Sell	250	$133.00	$33,250.00	16,862
3/1/2024	Jacqueline F. Moloney	Director	Sell	250	$122.89	$30,722.50	9,161
3/1/2024	Kathleen Flaherty Burke	EVP	Sell	7,411	$122.89	$910,737.79	42,999
2/22/2024	Seth H. Bagshaw	CFO	Sell	32,865	$123.28	$4,051,597.20	1
2/9/2024	Gerard G. Colella	Director	Sell	10,000	$120.00	$1,200,000.00	68,017
1/22/2024	Gerard G. Colella	Director	Sell	10,000	$110.00	$1,100,000.00	78,017
1/2/2024	Elizabeth Mora	Director	Sell	250	$100.90	$25,225.00	17,112
12/1/2023	Jacqueline F. Moloney	Director	Sell	250	$82.23	$20,557.50	11,328
11/7/2023	David Philip Henry	EVP	Buy	2,500	$68.34	$170,850.00	11,073

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

MKS Institutional Trading History

Reporting Date	Hedge Fund	Shares Held	Market Value	% of Portfolio	Quarterly Change in Shares	Ownership in Company
10/31/2026	Chicago Partners Investment Group LLC	3,210	$0.63M	0.0%	-22.6%	0.005%
10/30/2026	TT International Asset Management LTD	4,961	$1.32M	0.1%	+267.8%	0.007%
10/30/2026	Hiddenite Capital Partners LP	45,000	$11.94M	2.1%	+52.5%	0.067%
10/29/2026	Sumitomo Mitsui Trust Group Inc.	12,056	$3.20M	0.0%	+244.3%	0.018%
10/29/2026	Profund Advisors LLC	4,719	$1.25M	0.0%	-9.2%	0.007%
10/29/2026	ProShare Advisors LLC	9,768	$2.59M	0.0%	+33.9%	0.014%
10/29/2026	Vise Technologies Inc.	9,125	$2.42M	0.0%	+11.1%	0.013%
10/29/2026	State of Wyoming	6,410	$1.70M	0.1%	+35.3%	0.009%
10/28/2026	VIRGINIA RETIREMENT SYSTEMS ET Al	27,800	$7.38M	0.0%	+21.4%	0.041%
10/28/2026	China Universal Asset Management Co. Ltd.	5,950	$1.58M	0.1%	N/A	0.009%
10/28/2026	Childress Capital Advisors LLC	874	$0.23M	0.0%	N/A	0.001%
10/28/2026	North Dakota State Investment Board	2,054	$0.55M	0.0%	+2.9%	0.000%
10/28/2026	VestGen Advisors LLC	1,020	$0.27M	0.0%	-16.4%	0.000%
10/27/2026	Victory Financial Group LLC	1,187	$0.32M	0.0%	N/A	0.002%
10/26/2026	Park Avenue Securities LLC	1,603	$0.43M	0.0%	+12.5%	0.002%
10/26/2026	Verdence Capital Advisors LLC	13,594	$3.61M	0.2%	N/A	0.020%
10/26/2026	Maxi Investments CY Ltd	4,510	$1.20M	0.2%	+130.5%	0.007%
10/26/2026	Leo Wealth LLC	1,026	$0.27M	0.1%	N/A	0.002%
10/24/2026	Capelight Capital Asset Management LP	12,000	$3.18M	1.3%	N/A	0.018%
10/23/2026	Evergreen Capital Management LLC	3,171	$0.84M	0.0%	-3.7%	0.005%
10/23/2026	Sterling Capital Management LLC	8,216	$2.18M	0.0%	-36.8%	0.012%
10/23/2026	Inspire Investing LLC	15,352	$4.07M	0.2%	+390.9%	0.023%
10/22/2026	Yousif Capital Management LLC	17,579	$4.67M	0.1%	-5.8%	0.026%
10/22/2026	Brookstone Capital Management	1,188	$0.32M	0.0%	-83.1%	0.002%
10/22/2026	Root Financial Partners LLC	302	$80K	0.0%	N/A	0.000%
10/22/2026	Reyes Financial Architecture Inc.	240	$64K	0.0%	N/A	0.000%
10/21/2026	Cooke & Bieler LP	181,089	$48.05M	0.7%	+9.6%	0.268%
10/21/2026	Crossmark Global Holdings Inc.	4,428	$1.18M	0.0%	+14.5%	0.007%
10/21/2026	Capstone Capital Management Ltd	15,817	$4.20M	1.7%	+283.6%	0.023%
10/21/2026	Nisa Investment Advisors LLC	18,781	$4.98M	0.0%	+1.5%	0.028%
10/21/2026	Robeco Institutional Asset Management B.V.	80,051	$21.24M	0.0%	N/A	0.118%
10/20/2026	DUTCH ASSET Corp	2,530	$0.67M	0.3%	N/A	0.004%
10/19/2026	LexAurum Advisors LLC	1,200	$0.32M	0.0%	N/A	0.002%
10/17/2026	IFP Advisors Inc	359	$95K	0.0%	-17.3%	0.001%
10/16/2026	TD Waterhouse Canada Inc.	279	$76K	0.0%	+9,200.0%	0.000%
10/16/2026	Pension & Wealth Management Advisors Inc.	1,829	$0.49M	0.1%	N/A	0.003%
10/15/2026	V Square Quantitative Management LLC	183	$49K	0.0%	+64.9%	0.000%
10/15/2026	Assenagon Asset Management S.A.	442,273	$117.36M	0.1%	+1,742.1%	0.654%
10/15/2026	State of Alaska Department of Revenue	6,409	$1.70M	0.0%	-3.2%	0.009%
10/15/2026	Loftus Peak Pty Ltd	57,593	$15.28M	1.8%	+21.4%	0.085%
10/14/2026	First Citizens Bank & Trust Co.	2,166	$0.58M	0.0%	N/A	0.003%
10/13/2026	NorthCrest Asset Manangement LLC	1,262	$0.33M	0.0%	+19.5%	0.002%
10/9/2026	Wedmont Private Capital	4,193	$1.09M	0.0%	+2.3%	0.006%
10/9/2026	GAMMA Investing LLC	3,667	$0.97M	0.0%	+13.5%	0.005%
10/8/2026	Farther Finance Advisors LLC	500	$0.13M	0.0%	-56.4%	0.001%
10/8/2026	Artemis Investment Management LLP	85,330	$22.64M	0.2%	-39.9%	0.126%
10/8/2026	Whalen Wealth Management Inc.	871	$0.23M	0.1%	N/A	0.001%
10/5/2026	Neville Rodie & Shaw Inc.	2,545	$0.68M	0.0%	-41.6%	0.004%
10/5/2026	MassMutual Private Wealth & Trust FSB	1,318	$0.35M	0.0%	+9.9%	0.002%
9/23/2026	QRG Capital Management Inc.	4,121	$1.83M	0.0%	+7.4%	0.006%
9/23/2026	Envestnet Portfolio Solutions Inc.	594	$0.26M	0.0%	N/A	0.001%
9/15/2026	Reynders McVeigh Capital Management LLC	513	$0.23M	0.0%	N/A	0.001%
9/9/2026	Sequoia Financial Advisors LLC	1,961	$0.87M	0.0%	+35.7%	0.003%
9/9/2026	Tidal Investments LLC	44,846	$19.95M	0.0%	+42.2%	0.066%
9/9/2026	Arlington Capital Management Inc.	856	$0.38M	0.2%	N/A	0.001%
9/9/2026	BlueCrest Capital Management Ltd	19,705	$8.77M	0.3%	+11.8%	0.029%
9/9/2026	WINTON GROUP Ltd	6,203	$2.76M	0.1%	+287.7%	0.009%
9/9/2026	Engineers Gate Manager LP	4,399	$1.96M	0.0%	-77.8%	0.007%
9/9/2026	Pinnacle Wealth Management Advisory Group LLC	792	$0.35M	0.0%	N/A	0.001%
9/9/2026	Integrated Wealth Concepts LLC	2,195	$0.98M	0.0%	+6.9%	0.003%
9/9/2026	NewEdge Advisors LLC	6,724	$2.99M	0.0%	-72.6%	0.010%
9/9/2026	IFP Advisors Inc	434	$0.19M	0.0%	+129.6%	0.001%
9/9/2026	Baird Financial Group Inc.	2,252	$1M	0.0%	+2.9%	0.003%
9/8/2026	Allworth Financial LP	1,402	$0.62M	0.0%	+24.3%	0.002%
9/8/2026	Arizona State Retirement System	18,576	$8.26M	0.0%	+0.7%	0.027%
9/8/2026	West Family Investments Inc.	482	$0.21M	0.1%	N/A	0.001%
9/8/2026	Waverly Advisors LLC	846	$0.38M	0.0%	N/A	0.001%
9/8/2026	Nykredit A S	2,289	$1.02M	0.0%	N/A	0.003%
9/4/2026	Parkside Financial Bank & Trust	133	$59K	0.0%	-26.5%	0.000%
9/2/2026	Allianz Asset Management GmbH	34,970	$15.56M	0.0%	N/A	0.052%
8/27/2026	Corient Private Wealth LP	36,160	$16.08M	0.0%	+0.8%	0.053%
8/26/2026	HighTower Advisors LLC	5,565	$2.48M	0.0%	-55.1%	0.008%
8/25/2026	VIRGINIA RETIREMENT SYSTEMS ET Al	22,900	$10.19M	0.1%	N/A	0.034%
8/23/2026	Wedmont Private Capital	4,098	$1.82M	0.0%	+6.2%	0.006%
8/23/2026	HB Wealth Management LLC	2,752	$1.22M	0.0%	+35.3%	0.004%
8/23/2026	Angeles Wealth Management LLC	917	$0.41M	0.0%	+4.8%	0.001%
8/22/2026	AlphaGrep UK Ltd	862	$0.38M	0.1%	N/A	0.001%
8/22/2026	Oakmont Investment Advisors Inc.	500	$0.22M	0.2%	N/A	0.001%
8/22/2026	Syon Capital LLC	2,901	$1.29M	0.1%	-12.7%	0.004%
8/22/2026	Concurrent Investment Advisors LLC	939	$0.42M	0.0%	N/A	0.001%
8/21/2026	AXQ Capital LP	3,294	$1.47M	0.2%	-54.6%	0.005%
8/21/2026	Retireful LLC	3,342	$1.49M	1.4%	N/A	0.005%
8/21/2026	Greenspring Advisors LLC	483	$0.22M	0.0%	N/A	0.001%
8/21/2026	Nykredit A S	2,289	$1.02M	0.0%	N/A	0.003%
8/20/2026	Proficio Capital Partners LLC	1,054	$0.47M	0.0%	N/A	0.002%
8/20/2026	Spyglass Capital Management LLC	118,526	$52.72M	2.9%	N/A	0.175%
8/20/2026	Teza Capital Management LLC	1,084	$0.48M	0.9%	N/A	0.002%
8/20/2026	BTG Pactual Asset Management US LLC	532	$0.24M	0.0%	N/A	0.001%
8/20/2026	Senator Investment Group LP	65,000	$28.91M	1.1%	N/A	0.096%
8/20/2026	Sigma Planning Corp	1,706	$0.76M	0.0%	N/A	0.003%
8/20/2026	Benjamin Edwards Inc.	1,118	$0.50M	0.0%	-3.7%	0.002%
8/20/2026	Flputnam Investment Management Co.	485	$0.22M	0.0%	N/A	0.001%
8/20/2026	Northwestern Mutual Wealth Management Co.	173,207	$77.04M	0.0%	+76,880.9%	0.256%
8/19/2026	Hsbc Holdings PLC	56,935	$24.98M	0.0%	+2,274.3%	0.084%
8/19/2026	Archer Investment Corp	4,545	$2.02M	0.3%	N/A	0.007%
8/18/2026	Empowered Funds LLC	3,714	$1.65M	0.0%	N/A	0.005%
8/18/2026	United Capital Financial Advisors LLC	2,866	$1.28M	0.0%	N/A	0.004%
8/18/2026	Jefferies Financial Group Inc.	1,023	$0.46M	0.0%	N/A	0.002%
8/18/2026	Public Employees Retirement System of Ohio	38,346	$17.06M	0.1%	N/A	0.057%
8/17/2026	Capstone Investment Advisors LLC	628	$0.28M	0.0%	N/A	0.001%

Data available starting January 2016

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.

Today's Range

Now: $202.04

$196.20

$206.85

50 Day Range

MA: $248.05

$196.11

$281.41

52 Week Range

Now: $202.04

$134.74

$447.62

Volume

1,384,758 shs

Average Volume

1,338,481 shs

Market Capitalization

$13.66 billion

P/E Ratio

32.22

Dividend Yield

0.49%

Beta

2.14

Who are the company insiders with the largest holdings of MKS?: MKS's top insider investors include:
Carlyle Partners Vi Cayman Hol (Major Shareholder)
John Tseng-Chung Lee (CEO)
Leo Berlinghieri (CEO)
Gerard G Colella (Director)
Gerard G Colella (CEO)
Kathleen Flaherty Burke (EVP)
Gerald G Colella (Director)
Seth H Bagshaw (CFO)
Seth H Bagshaw (CFO)
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:
Assenagon Asset Management S.A. — 0.65%
Cooke & Bieler LP — 0.27%
Artemis Investment Management LLP — 0.13%
Robeco Institutional Asset Management B.V. — 0.12%
Loftus Peak Pty Ltd — 0.09%
Hiddenite Capital Partners LP — 0.07%
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:
Artemis Investment Management LLP
Brookstone Capital Management
Sterling Capital Management LLC
Neville Rodie & Shaw Inc.
Yousif Capital Management LLC
Chicago Partners Investment Group LLC
Farther Finance Advisors LLC
Profund Advisors LLC
Within the previous year, company insiders that have sold MKS company stock include:
John Tseng-Chung Lee (CEO)
Kathleen Flaherty Burke (EVP)
Gerald G Colella (Director)
Eric Robert Taranto (EVP)
Elizabeth Mora (Director)
David Philip Henry (EVP)
Jacqueline F Moloney (Director)
Joseph B Donahue (Director)
Peter Cannone III (Director)
John Edward Williams (EVP)
Michelle M Mccarthy (CAO)
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:
Assenagon Asset Management S.A.
Robeco Institutional Asset Management B.V.
Cooke & Bieler LP
Hiddenite Capital Partners LP
Verdence Capital Advisors LLC
Inspire Investing LLC
Capelight Capital Asset Management LP
Capstone Capital Management Ltd