MKSI Insider Trading

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Insider Trading History
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About

Insider Ownership Percentage: 0.57%

Insider Buying (Last 12 Months): $0.00

Insider Selling (Last 12 Months): $18,289,968.89

MKS Insider Trading History Chart

MKS Share Price & Price History

^$287.65

▼ -3.88 (-1.33%)

As of 05/5/2026 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
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
10/2/2023	Elizabeth Mora	Director	Sell	250	$87.15	$21,787.50	17,362
9/6/2023	Seth H. Bagshaw	CFO	Sell	25,000	$97.30	$2,432,500.00	20,547
8/31/2023	Gerard G. Colella	Director	Sell	10,000	$100.01	$1,000,100.00	88,017
8/28/2023	Jacqueline F. Moloney	Director	Sell	250	$95.25	$23,812.50	11,578
8/7/2023	Kathleen Flaherty Burke	EVP	Sell	11,563	$101.23	$1,170,522.49	42,738
7/3/2023	Elizabeth Mora	Director	Sell	250	$108.49	$27,122.50	17,612
6/1/2023	Elizabeth Mora	Director	Sell	200	$97.16	$19,432.00	17,862
5/8/2023	Carlyle Partners Vi Cayman Hol	Major Shareholder	Sell	2,000,000	$86.12	$172,240,000.00	6,482,732

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
5/5/2026	Sanctuary Advisors LLC	7,342	$1.69M	0.0%	-19.1%	0.011%
5/4/2026	Empirical Financial Services LLC d.b.a. Empirical Wealth Management	2,165	$0.50M	0.0%	N/A	0.003%
5/4/2026	Archer Investment Corp	5,066	$1.16M	0.2%	+27.6%	0.008%
5/4/2026	State of Michigan Retirement System	16,140	$3.71M	0.0%	+1.9%	0.024%
5/4/2026	Principal Financial Group Inc.	614,230	$141.16M	0.1%	-19.8%	0.912%
5/4/2026	Chicago Partners Investment Group LLC	3,384	$0.78M	0.0%	+57.1%	0.005%
5/4/2026	Teachers Retirement System of The State of Kentucky	32,572	$7.49M	0.1%	-14.1%	0.048%
5/1/2026	Fifth Third Bancorp	19,294	$4.43M	0.0%	+3,011.9%	0.029%
5/1/2026	Sequoia Financial Advisors LLC	1,445	$0.33M	0.0%	-29.0%	0.002%
4/30/2026	Equitable Trust Co.	7,224	$1.66M	0.1%	-38.5%	0.011%
4/30/2026	Hsbc Holdings PLC	2,398	$0.55M	0.0%	-74.5%	0.004%
4/30/2026	Mitsubishi UFJ Morgan Stanley Securities Co. Ltd.	1,388	$0.32M	0.8%	N/A	0.002%
4/30/2026	Oregon Public Employees Retirement Fund	13,766	$3.16M	0.0%	+2.8%	0.020%
4/30/2026	Quantum Portfolio Management LLC	1,394	$0.32M	0.0%	-51.7%	0.002%
4/29/2026	Childress Capital Advisors LLC	872	$0.20M	0.0%	N/A	0.001%
4/29/2026	Resonant Capital Advisors LLC	1,250	$0.29M	0.0%	N/A	0.002%
4/29/2026	Burney Co.	1,360	$0.31M	0.0%	+7.1%	0.002%
4/28/2026	Whittier Trust Co. of Nevada Inc.	145	$34K	0.0%	-32.9%	0.000%
4/28/2026	Hudson Edge Investment Partners Inc.	3,813	$0.88M	0.1%	-39.6%	0.006%
4/28/2026	QRG Capital Management Inc.	3,836	$0.88M	0.0%	-14.8%	0.006%
4/27/2026	HB Wealth Management LLC	2,034	$0.47M	0.0%	N/A	0.003%
4/27/2026	Counterpoint Mutual Funds LLC	2,430	$0.56M	0.1%	+25.1%	0.004%
4/27/2026	World Investment Advisors	1,226	$0.28M	0.0%	-7.1%	0.002%
4/27/2026	New York State Teachers Retirement System	63,109	$14.50M	0.0%	-3.3%	0.094%
4/27/2026	Sierra Summit Advisors LLC	4,879	$1.12M	0.2%	N/A	0.007%
4/27/2026	Private Advisor Group LLC	3,144	$0.72M	0.0%	-24.1%	0.005%
4/27/2026	Y Intercept Hong Kong Ltd	9,732	$2.24M	0.0%	N/A	0.014%
4/27/2026	Leonteq Securities AG	1,179	$0.27M	0.0%	+66.8%	0.002%
4/27/2026	Fideuram Intesa Sanpaolo Private Banking S.P.A.	2,624	$0.60M	0.0%	N/A	0.004%
4/25/2026	Strs Ohio	45,201	$10.39M	0.0%	-44.1%	0.067%
4/25/2026	Keybank National Association OH	1,308	$0.30M	0.0%	N/A	0.002%
4/24/2026	Root Financial Partners LLC	273	$63K	0.0%	+93.6%	0.000%
4/24/2026	Fulton Bank N.A.	3,228	$0.74M	0.0%	-17.6%	0.005%
4/23/2026	Inspire Investing LLC	9,419	$2.17M	0.2%	-14.0%	0.014%
4/22/2026	Janney Montgomery Scott LLC	8,650	$1.99M	0.0%	-47.5%	0.013%
4/22/2026	Pictet Asset Management Holding SA	10,903	$2.51M	0.0%	+6.4%	0.016%
4/22/2026	Sterling Capital Management LLC	7,058	$1.62M	0.0%	-58.5%	0.010%
4/22/2026	Venturi Wealth Management LLC	2,736	$0.63M	0.0%	-36.6%	0.004%
4/21/2026	GHP Investment Advisors Inc.	50,487	$11.60M	0.5%	+6.2%	0.075%
4/21/2026	Aaron Wealth Advisors LLC	3,928	$0.90M	0.1%	-26.9%	0.006%
4/21/2026	Louisiana State Employees Retirement System	19,500	$4.48M	0.1%	N/A	0.029%
4/21/2026	Fairvoy Private Wealth LLC	3,070	$0.71M	0.2%	N/A	0.005%
4/20/2026	Blue Trust Inc.	4,274	$0.98M	0.0%	+1.1%	0.006%
4/20/2026	Fifth Third Wealth Advisors LLC	2,087	$0.48M	0.0%	+4.1%	0.003%
4/20/2026	OP Asset Management Ltd	2,828	$0.65M	0.0%	N/A	0.004%
4/20/2026	Assenagon Asset Management S.A.	36,911	$8.48M	0.0%	-60.2%	0.055%
4/18/2026	Bourne Lent Asset Management Inc.	929	$0.21M	0.1%	N/A	0.001%
4/18/2026	Steph & Co.	962	$0.22M	0.1%	-17.2%	0.001%
4/17/2026	Hanson & Doremus Investment Management	6,853	$1.58M	0.2%	+14.1%	0.010%
4/16/2026	SG Americas Securities LLC	110,343	$25.36M	0.0%	+477.0%	0.164%
4/16/2026	Evolve Private Wealth LLC	931	$0.21M	0.0%	N/A	0.001%
4/16/2026	Diversified Trust Co	1,675	$0.39M	0.0%	N/A	0.002%
3/20/2026	Hsbc Holdings PLC	9,390	$1.51M	0.0%	-50.0%	0.014%
3/17/2026	Rockefeller Capital Management L.P.	557	$89K	0.0%	+34.2%	0.001%
3/13/2026	World Investment Advisors	1,319	$0.21M	0.0%	-18.5%	0.002%
3/9/2026	Corient Private Wealth LLC	11,855	$1.90M	0.0%	+102.3%	0.018%
3/6/2026	Hsbc Holdings PLC	9,390	$1.51M	0.0%	-50.0%	0.014%
2/26/2026	Alpine Global Management LLC	4,000	$0.64M	0.1%	N/A	0.006%
2/24/2026	Pacer Advisors Inc.	10,691	$1.71M	0.0%	-11.0%	0.016%
2/23/2026	Kera Capital Partners Inc.	2,292	$0.37M	0.0%	N/A	0.003%
2/23/2026	Virtu Financial LLC	7,295	$1.17M	0.0%	N/A	0.011%
2/20/2026	Dean Capital Management	12,090	$1.93M	0.8%	+3.2%	0.018%
2/19/2026	Corient Private Wealth LLC	133,036	$21.26M	0.0%	+2,170.2%	0.198%
2/18/2026	Mercer Global Advisors Inc. ADV	10,968	$1.75M	0.0%	+48.0%	0.016%
2/18/2026	Vident Advisory LLC	2,190	$0.35M	0.0%	-9.0%	0.003%
2/18/2026	State of Tennessee Department of Treasury	29,270	$4.68M	0.0%	-12.6%	0.044%
2/18/2026	EP Wealth Advisors LLC	4,384	$0.70M	0.0%	N/A	0.007%
2/18/2026	Mackenzie Financial Corp	4,175	$0.67M	0.0%	N/A	0.006%
2/18/2026	NewEdge Advisors LLC	2,659	$0.43M	0.0%	N/A	0.004%
2/18/2026	Empowered Funds LLC	3,699	$0.59M	0.0%	-10.3%	0.006%
2/18/2026	XTX Topco Ltd	19,944	$3.19M	0.1%	N/A	0.030%
2/18/2026	SummitTX Capital L.P.	205,750	$32.88M	1.0%	+4.6%	0.306%
2/18/2026	Polymer Capital Management US LLC	2,425	$0.39M	0.0%	N/A	0.004%
2/18/2026	Old West Investment Management LLC	16,350	$2.61M	0.5%	+3.2%	0.024%
2/18/2026	Millennium Management LLC	817,251	$130.60M	0.1%	+83.1%	1.217%
2/18/2026	Infrastructure Capital Advisors LLC	3,572	$0.57M	0.1%	-22.2%	0.005%
2/18/2026	Inspire Investing LLC	10,946	$1.75M	0.2%	+197.4%	0.016%
2/18/2026	Gotham Asset Management LLC	225,215	$35.99M	0.1%	+13.1%	0.335%
2/18/2026	Engineers Gate Manager LP	12,231	$1.96M	0.0%	+212.5%	0.018%
2/18/2026	Expect Equity LLC	24,015	$3.84M	3.7%	-23.7%	0.036%
2/18/2026	Cinctive Capital Management LP	31,897	$5.10M	0.3%	N/A	0.047%
2/18/2026	Concentric Capital Strategies LP	102,590	$16.39M	0.8%	+36.9%	0.153%
2/18/2026	Balyasny Asset Management L.P.	511,620	$81.76M	0.1%	-39.8%	0.762%
2/17/2026	Guggenheim Capital LLC	9,812	$1.57M	0.0%	+1.7%	0.015%
2/17/2026	AQR Arbitrage LLC	40,090	$6.41M	0.1%	-65.8%	0.060%
2/17/2026	Integrated Advisors Network LLC	1,779	$0.28M	0.0%	N/A	0.003%
2/17/2026	AQR Capital Management LLC	196,662	$31.43M	0.0%	+15.7%	0.293%
2/17/2026	Aequim Alternative Investments LP	28,189	$4.51M	0.1%	N/A	0.042%
2/17/2026	Cetera Investment Advisers	27,051	$4.32M	0.0%	+2.1%	0.040%
2/17/2026	Defiance ETFs LLC	237,906	$38.50M	1.3%	N/A	0.354%
2/17/2026	Southpoint Capital Advisors LP	600,000	$95.88M	2.2%	N/A	0.893%
2/17/2026	Jain Global LLC	127,003	$20.30M	0.1%	-4.7%	0.189%
2/17/2026	Park West Asset Management LLC	278,614	$44.52M	3.7%	+364.4%	0.415%
2/17/2026	Quantedge Capital Pte Ltd	4,000	$0.64M	0.3%	N/A	0.006%
2/17/2026	Trexquant Investment LP	9,159	$1.46M	0.0%	+27.1%	0.014%
2/17/2026	Price T Rowe Associates Inc. MD	2,753,850	$440.07M	0.0%	-24.2%	4.100%
2/17/2026	Watershed Asset Management L.L.C.	2,902	$0.46M	0.4%	N/A	0.004%
2/17/2026	Dean Investment Associates LLC	23,480	$3.75M	0.5%	+2.7%	0.035%
2/17/2026	Osaic Holdings Inc.	5,196	$0.83M	0.0%	+2.2%	0.008%
2/17/2026	Public Employees Retirement System of Ohio	55,319	$8.84M	0.0%	-11.2%	0.082%

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: $287.65

$280.18

$298.00

50 Day Range

MA: $246.76

$210.00

$283.75

52 Week Range

Now: $287.65

$71.49

$298.00

Volume

1,536,252 shs

Average Volume

1,393,200 shs

Market Capitalization

$19.36 billion

P/E Ratio

65.82

Dividend Yield

0.36%

Beta

1.98

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:
Principal Financial Group Inc. — 0.91%
SG Americas Securities LLC — 0.16%
New York State Teachers Retirement System — 0.09%
GHP Investment Advisors Inc. — 0.07%
Strs Ohio — 0.07%
Assenagon Asset Management S.A. — 0.05%
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:
Principal Financial Group Inc.
Assenagon Asset Management S.A.
Strs Ohio
Sterling Capital Management LLC
Janney Montgomery Scott LLC
Hsbc Holdings PLC
Teachers Retirement System of The State of Kentucky
Equitable Trust Co.
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)
David Philip Henry (EVP)
Eric Robert Taranto (EVP)
Elizabeth Mora (Director)
Jacqueline F Moloney (Director)
Peter Cannone III (Director)
John Edward Williams (EVP)
Michelle M Mccarthy (CAO)
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:
SG Americas Securities LLC
Louisiana State Employees Retirement System
Fifth Third Bancorp
Y Intercept Hong Kong Ltd
Sierra Summit Advisors LLC
Fairvoy Private Wealth LLC
GHP Investment Advisors Inc.
OP Asset Management Ltd