MKS INSTRS INC

Ticker: MKSI CUSIP: 55306N104 Class: EQTY

Polaris Capital Management, LLC's Holding History (CIK: 0001316926)

Note: Option positions (PUT/CALL) are excluded.

Q4 2025

Shares 265,100 Value ($000) $42,363 Avg Close $148.21 Range $120.73 - $170.37

Q3 2025

Shares 401,300 Value ($000) $49,669 Avg Close $106.31 Range $88.17 - $132.24

Q2 2025

Shares 361,400 Value ($000) $35,909 Avg Close $80.86 Range $54.50 - $100.44

Q1 2025

Shares 373,600 Value ($000) $29,944 Avg Close $100.21 Range $75.89 - $124.28

Q4 2024

Shares 352,400 Value ($000) $36,787 Avg Close $106.91 Range $96.54 - $118.37

Q3 2024

Shares 354,000 Value ($000) $38,483 Avg Close $117.45 Range $99.10 - $145.63

Q2 2024

Shares 358,600 Value ($000) $46,826 Avg Close $124.55 Range $105.72 - $137.52

Q1 2024

Shares 366,700 Value ($000) $48,771 Avg Close $114.51 Range $94.23 - $132.85

Q4 2023

Shares 534,000 Value ($000) $54,933 Avg Close $79.84 Range $62.28 - $104.49

Q3 2023

Shares 461,300 Value ($000) $39,921 Avg Close $95.58 Range $81.25 - $107.67

Q2 2023

Shares 645,700 Value ($000) $69,800 Avg Close $89.53 Range $77.81 - $108.20

Q1 2023

Shares 650,800 Value ($000) $57,674 Avg Close $93.12 Range $80.00 - $111.27

Q4 2022

Shares 581,600 Value ($000) $49,279 Avg Close $78.00 Range $62.97 - $89.22

Q3 2022

Shares 10,700 Value ($000) $884 Avg Close $100.01 Range $79.23 - $120.27

Q2 2022

Shares 745,494 Value ($000) $63,740 Avg Close $112.92 Range $94.75 - $148.07

Q1 2022

Shares 5,300 Value ($000) $795 Avg Close $150.35 Range $131.30 - $175.09

Q4 2021

Shares 8,500 Value ($000) $1,480 Avg Close $151.09 Range $136.06 - $172.80

Q3 2021

Shares 8,500 Value ($000) $1,283 Avg Close $148.13 Range $133.76 - $168.78

Q2 2021

Shares 8,500 Value ($000) $1,513 Avg Close $175.09 Range $158.98 - $192.11

Q1 2021

Shares 8,500 Value ($000) $1,483 Avg Close $161.78 Range $138.78 - $185.00

Q4 2020

Shares 11,000 Value ($000) $1,655 Avg Close $125.75 Range $101.82 - $152.08

Q3 2020

Shares 11,000 Value ($000) $1,202 Avg Close $112.47 Range $97.77 - $124.64

Q2 2020

Shares 12,600 Value ($000) $1,427 Avg Close $95.31 Range $70.45 - $112.06

Q1 2020

Shares 15,800 Value ($000) $1,287 Avg Close $97.84 Range $64.00 - $116.86

Period	Shares	Value ($000)	Average Close	Price Range
Q4 2025	265,100	$42,363	$148.21	$120.73 - $170.37
Q3 2025	401,300	$49,669	$106.31	$88.17 - $132.24
Q2 2025	361,400	$35,909	$80.86	$54.50 - $100.44
Q1 2025	373,600	$29,944	$100.21	$75.89 - $124.28
Q4 2024	352,400	$36,787	$106.91	$96.54 - $118.37
Q3 2024	354,000	$38,483	$117.45	$99.10 - $145.63
Q2 2024	358,600	$46,826	$124.55	$105.72 - $137.52
Q1 2024	366,700	$48,771	$114.51	$94.23 - $132.85
Q4 2023	534,000	$54,933	$79.84	$62.28 - $104.49
Q3 2023	461,300	$39,921	$95.58	$81.25 - $107.67
Q2 2023	645,700	$69,800	$89.53	$77.81 - $108.20
Q1 2023	650,800	$57,674	$93.12	$80.00 - $111.27
Q4 2022	581,600	$49,279	$78.00	$62.97 - $89.22
Q3 2022	10,700	$884	$100.01	$79.23 - $120.27
Q2 2022	745,494	$63,740	$112.92	$94.75 - $148.07
Q1 2022	5,300	$795	$150.35	$131.30 - $175.09
Q4 2021	8,500	$1,480	$151.09	$136.06 - $172.80
Q3 2021	8,500	$1,283	$148.13	$133.76 - $168.78
Q2 2021	8,500	$1,513	$175.09	$158.98 - $192.11
Q1 2021	8,500	$1,483	$161.78	$138.78 - $185.00
Q4 2020	11,000	$1,655	$125.75	$101.82 - $152.08
Q3 2020	11,000	$1,202	$112.47	$97.77 - $124.64
Q2 2020	12,600	$1,427	$95.31	$70.45 - $112.06
Q1 2020	15,800	$1,287	$97.84	$64.00 - $116.86