MKS Inc.
US ˙ NasdaqGS ˙ US55306N1046

SecurityMKSI / MKS Inc.
InstitutionShell Asset Management Co
Latest Disclosed Ownership876 shares
Latest Disclosed Value $ 108
Shell Asset Management Co reports 60.36% decrease in ownership of MKSI / MKS Inc.

On November 7, 2025 - Shell Asset Management Co filed a 13F-HR form disclosing ownership of 876 shares of MKS Inc. (US:MKSI) valued at $108,423 USD as of September 30, 2025. The entity filed a previous 13F-HR on July 23, 2025 disclosing 2,210 shares of MKS Inc.. The current value of the position is $264,245 USD.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date		 Effective
Date		Form Security Class ID Avg Price
Paid (Est)		 Reported
Shares		 ΔShares ΔShares
(%)		 Reported
Value
(x1000)		 ΔValue
(%)		 Alloc
(%)		 ΔAlloc ΔAlloc (%) Cost Basis
(x1000)		 Unrealized
Gain/Loss
(x1000)
2025-11-07 2025-09-30 13F MKS COM 55306N104 876 -1,334 -60.36 0 0.0108
2025-07-23 2025-06-30 13F MKS COM 55306N104 2,210 -490 -18.15 0 0.0076
2025-05-14 2025-03-31 13F MKS INSTRS COM 55306N104 2,700 -117 -4.15 0 0.0103
2025-02-14 2024-12-31 13F MKS INSTRS COM 55306N104 2,817 -6 -0.21 0 0.0128
2024-11-07 2024-09-30 13F MKS INSTRS COM 55306N104 2,823 -164 -5.49 0 0.0135
2024-07-25 2024-03-31 13F MKS INSTRS COM 55306N104 2,987 -306 -9.29 0 0.0178
2024-02-14 2023-12-31 13F MKS INSTRS COM 55306N104 3,293 -966 -22.68 0 0.0157
2023-11-08 2023-09-30 13F MKS INSTRS COM 55306N104 4,259 -75 -1.73 0 0.0152
2023-07-28 2023-06-30 13F MKS INSTRS COM 55306N104 4,334 -25 -0.57 0 0.0185
2023-05-15 2023-03-31 13F MKS INSTRS COM 55306N104 4,359 -15 -0.34 0 0.0160
2023-02-07 2022-12-31 13F MKS INSTRS COM 55306N104 4,374 -886 -16.84 0 -100.00 0.0163
2022-11-14 2022-09-30 13F MKS INSTRS COM 55306N104 5,260 -1,385 -20.84 435 -36.22 0.0170
2022-08-09 2022-06-30 13F MKS INSTRS COM 55306N104 6,645 1,671 33.59 682 -8.58 0.0202
2022-05-04 2022-03-31 13F MKS INSTRS COM 55306N104 4,974 -738 -12.92 746 -25.03 0.0176
2022-02-09 2021-12-31 13F MKS INSTRS COM 55306N104 5,712 33 0.58 995 16.10 0.0204
2021-11-04 2021-09-30 13F MKS INSTRS COM 55306N104 5,679 -230 -3.89 857 -18.54 0.0192
2021-08-12 2021-06-30 13F MKS INSTRS COM 55306N104 5,909 330 5.92 1,052 1.74 0.0204
2021-05-10 2021-03-31 13F MKS INSTRS COM 55306N104 5,579 1,445 34.95 1,034 66.24 0.0207
2021-02-16 2020-12-31 13F MKS INSTRS COM 55306N104 4,134 0 0.00 622 37.61 0.0128
2020-11-13 2020-09-30 13F MKS INSTRS COM 55306N104 4,134 0 0.00 452 -3.42 0.0105
2020-08-10 2020-06-30 13F MKS INSTRS COM 55306N104 4,134 -84 -1.99 468 36.05 0.0117
2020-05-11 2020-03-31 13F MKS INSTRS COM 55306N104 4,218 -65 -1.52 344 -26.96 0.0096
2020-02-13 2019-12-31 13F MKS INSTRUMENT COM 55306N104 4,283 -130 -2.95 471 15.72 0.0101
2019-11-12 2019-09-30 13F MKS INSTRUMENT COM 55306N104 4,413 -11,867 -72.89 407 -67.90 0.0093
2019-08-12 2019-06-30 13F MKS INSTRUMENT COM 55306N104 16,280 -372 -2.23 1,268 -18.14 0.0281
2019-05-09 2019-03-31 13F MKS INSTRUMENT COM 55306N104 16,652 0 0.00 1,549 43.96 0.0342
2019-02-13 2018-12-31 13F MKS INSTRUMENT COM 55306N104 16,652 -1,400 -7.76 1,076 -25.64 0.0268
2018-11-13 2018-09-30 13F MKS INSTRUMENT COM 55306N104 18,052 0 0.00 1,447 -16.26 0.0286
2018-08-10 2018-06-30 13F MKS INSTRUMENT COM 55306N104 18,052 -968 -5.09 1,728 -21.45 0.0354
2018-05-14 2018-03-31 13F MKS INSTRUMENT COM 55306N104 19,020 0 0.00 2,200 22.43 0.0438
2018-02-09 2017-12-31 13F MKS INSTRUMENT COM 55306N104 19,020 0 0.00 1,797 0.06 0.0357
2017-10-20 2017-09-30 13F/A-1 MKS INSTRUMENT COM 55306N104 19,020 -500 -2.56 1,796 36.68 0.0399
2017-07-26 2017-06-30 13F MKS INSTRUMENT COM 55306N104 19,520 0 0.00 1,314 -2.09 0.0326
2017-04-26 2017-03-31 13F MKS INSTRUMENT COM 55306N104 19,520 -1,367 -6.54 1,342 8.14 0.0343
2017-01-10 2016-12-31 13F MKS INSTRUMENT COM 55306N104 20,887 -182 -0.86 1,241 18.42 0.0336
2016-10-28 2016-09-30 13F MKS INSTRUMENT COM 55306N104 21,069 -967 -4.39 1,048 10.43 0.0251
2016-07-25 2016-06-30 13F MKS INSTRUMENT COM 55306N104 22,036 -1,256 -5.39 949 8.21 0.0220
2016-05-11 2016-03-31 13F MKS INSTRUMENT COM 55306N104 23,292 -1,399 -5.67 877 -1.35 0.0210
2016-02-05 2015-12-31 13F MKS INSTRUMENT COM 55306N104 24,691 24,691 0.00 889 0.0210
2015-10-13 2015-09-30 13F MKS INSTRUMENT COM 55306N104 0 -25,013 -100.00 0 -100.00
2015-07-30 2015-06-30 13F MKS INSTRUMENT COM 55306N104 25,013 -1,140 -4.36 949 7.35 0.0190
2015-05-07 2015-03-31 13F MKS INSTRUMENT COM 55306N104 26,153 26,153 884 0.0154
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.