MKS INC. MKSI
COM · Common Stock · CUSIP 55306N104 · ISIN US55306N1046
Company in Andover, United States
* Summed across managers. Shares that two managers' reports both contain – a subsidiary's holdings that its parent's report includes too, or a sub-adviser's in its client's – are counted once ($43.4m this quarter). Holder counts are more reliable. Shares outstanding: 67.2m as of 2025-10-28, from the company's own SEC filing; the percentage can still exceed 100%: lent-out shares are counted by the lender and the buyer, and some reports overlap without saying so. Implied quarter-end price ≈ $159.63. Options: 14 managers hold calls ($339.9m notional), 12 hold puts ($58.0m).
Trends to Q4 2025
Institutional holders
Managers reporting a position, each quarter
Numbers
| Quarter | Holders |
|---|---|
| Q3 2022 | 357 |
| Q4 2022 | 316 |
| Q1 2023 | 325 |
| Q2 2023 | 321 |
| Q3 2023 | 324 |
| Q4 2023 | 325 |
| Q1 2024 | 343 |
| Q2 2024 | 397 |
| Q3 2024 | 410 |
| Q4 2024 | 419 |
| Q1 2025 | 399 |
| Q2 2025 | 397 |
| Q3 2025 | 435 |
| Q4 2025 | 516 |
Buyers vs sellers
Managers adding to or starting a position, vs cutting or selling out
Numbers
| Quarter | Bought or added | Cut or sold out |
|---|---|---|
| Q1 2024 | 177 | 142 |
| Q2 2024 | 223 | 148 |
| Q3 2024 | 244 | 163 |
| Q4 2024 | 215 | 181 |
| Q1 2025 | 223 | 197 |
| Q2 2025 | 224 | 205 |
| Q3 2025 | 225 | 176 |
| Q4 2025 | 284 | 185 |
Calls vs puts
Options held, notional value, last 4 quarters. P/C = puts ÷ calls
Numbers
| Quarter | Calls | Puts | P/C |
|---|---|---|---|
| Q1 2025 | $155.0m | $16.4m | 0.11 |
| Q2 2025 | $201.8m | $25.2m | 0.12 |
| Q3 2025 | $261.2m | $44.3m | 0.17 |
| Q4 2025 | $339.9m | $58.0m | 0.17 |
Biggest buyers
| Invesco Ltd. | Added | +1.5m |
| Southpoint Capital Advisors LP | New | +600.0k |
| WESTFIELD CAPITAL MANAGEMENT CO LP | Added | +516.4k |
| AMERICAN CENTURY COMPANIES INC | Added | +395.4k |
| MILLENNIUM MANAGEMENT LLC | Added | +371.0k |
| CITADEL ADVISORS LLC | Added | +316.7k |
| JANE STREET GROUP, LLC | Added | +251.5k |
| CRAMER ROSENTHAL MCGLYNN LLC | New | +230.7k |
| JPMORGAN CHASE & CO | Added | +222.3k |
| Park West Asset Management LLC | Added | +218.6k |
Biggest sellers
| VICTORY CAPITAL MANAGEMENT INC | Reduced | -1.0m |
| NORDEA INVESTMENT MANAGEMENT AB | Reduced | -996.6k |
| PRICE T ROWE ASSOCIATES INC /MD/ | Reduced | -879.2k |
| FRONTIER CAPITAL MANAGEMENT CO LLC | Reduced | -530.0k |
| WELLINGTON MANAGEMENT GROUP LLP | Reduced | -461.8k |
| Point72 Asset Management, L.P. | Reduced | -387.8k |
| Capital Research Global Investors | Sold out | -387.2k |
| ROYAL BANK OF CANADA | Reduced | -370.0k |
| FRANKLIN RESOURCES INC | Reduced | -367.2k |
| COOKE & BIELER LP | Reduced | -355.2k |
Biggest calls
| UBS Group AG | Unchanged | $145.0m907.2k shares |
| JANE STREET GROUP, LLC | Reduced | $86.2m539.3k shares |
| PEAK6 LLC | Added | $36.5m228.2k shares |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Added | $32.2m201.7k shares |
| NOMURA HOLDINGS INC | New | $10.7m66.8k shares |
| Caption Management, LLC | Unchanged | $10.4m65.0k shares |
| CITADEL ADVISORS LLC | Reduced | $7.2m44.8k shares |
| SIMPLEX TRADING, LLC | Added | $5.7m35.6k shares |
| Parallax Volatility Advisers, L.P. | New | $2.4m15.0k shares |
| IMC-Chicago, LLC | Reduced | $2.0m12.3k shares |
Biggest puts
| SUMMIT PARTNERS PUBLIC ASSET MANAGEMENT, LLC | Reduced | $20.6m129.0k shares |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Added | $11.5m71.9k shares |
| NOMURA HOLDINGS INC | New | $10.7m66.8k shares |
| CITADEL ADVISORS LLC | Added | $7.0m43.8k shares |
| PEAK6 LLC | New | $2.9m18.0k shares |
| JANE STREET GROUP, LLC | Added | $2.1m13.0k shares |
| AMERIPRISE FINANCIAL INC | Reduced | $1.9m11.6k shares |
| Walleye Trading LLC | Reduced | $1.0m6.3k shares |
| GROUP ONE TRADING LLC | Reduced | $175.8k1.1k shares |
| SIMPLEX TRADING, LLC | Reduced | $175.8k1.1k shares |
Options at notional value: the value of the shares the contracts control, as filers report them, not what the options cost. Not included in the holders, shares or buying above.
Major shareholders (over 5%)
Anyone who owns more than 5% of a class of the company's shares has to say so: on Schedule 13D if they may try to influence or control the company, on 13G if they're a passive investor, and update it as the stake changes. Each holder's latest filing, from 19 Dec 2024 on; percentages are of the share class, as the holder worked them out.
| Holder | Stake |
|---|---|
| BlackRock, Inc. 13G · institution filed 2025-10-17 | 8.8% |
| Invesco Ltd. 13G · institution new · filed 2026-02-12 | 6.5% |
| VANGUARD PORTFOLIO MANAGEMENT LLC 13G · institution new · filed 2026-04-29 | 5.5% |
| VANGUARD CAPITAL MANAGEMENT LLC 13G · institution new · filed 2026-04-30 | 5.2% |
Fell to 5% or below in the last year: JPMORGAN CHASE & CO (2.9%, 2026-09-03), VICTORY CAPITAL MANAGEMENT INC (90.0%, 2026-07-24), FMR LLC (3.3%, 2026-05-06), VANGUARD GROUP INC (0.0%, 2026-03-27; now reported by VANGUARD PORTFOLIO MANAGEMENT LLC), PRICE T ROWE ASSOCIATES INC /MD/ (4.1%, 2026-02-17)
Insider purchases and sales in Q4 2025
Shares bought or sold by the company's own officers, directors and 10% owners, in the open market or privately, as they reported to the SEC on Form 4 (due within two business days of the trade). Grants, option exercises, shares withheld for tax and gifts aren't included.
Officers and directors buying vs selling
Number of people, by quarter (10% owners not included)
Numbers
| Quarter | Buying | Bought | Selling | Sold | Sold under a plan |
|---|---|---|---|---|---|
| Q1 2024 | 0 | — | 5 | $7.6m | $2.4m |
| Q2 2024 | 0 | — | 1 | $68.8k | $68.8k |
| Q3 2024 | 0 | — | 3 | $276.4k | $62.8k |
| Q4 2024 | 0 | — | 2 | $92.9k | $92.9k |
| Q1 2025 | 0 | — | 3 | $889.4k | $53.2k |
| Q2 2025 | 0 | — | 1 | $24.5k | $24.5k |
| Q3 2025 | 0 | — | 4 | $1.1m | $1.1m |
| Q4 2025 | 0 | — | 3 | $182.9k | $182.9k |
| Date | Insider | Trade | Value |
|---|---|---|---|
| 2025-12-02 | Mora Elizabeth Director | Sold plan | $47.6k300 shares |
| 2025-10-22 | Schreiner James Alan EVP & COO | Sold plan | $98.6k711 shares |
| 2025-10-01 | Moloney Jacqueline F Director | Sold plan | $36.6k300 shares |
Their holding: how much the trade added to or took from the insider's holding (direct, or the trust or fund named). The same trade is sometimes reported by more than one insider, such as a fund and the director who represents it; totals count it once. A value is left blank where the reported price is far from the market price (usually a typo).
Holders, Q4 2025
| Manager | Shares | Change |
|---|---|---|
| VANGUARD GROUP INC 0.02% of their portfolio | 7.5m $1.2bn | Reduced -264.8k |
| BlackRock, Inc. 0.02% of their portfolio | 6.1m $981.0m | Added +15.5k |
| Invesco Ltd. 0.06% of their portfolio | 3.9m $616.1m | Added +1.5m |
| Capital International Investors 0.08% of their portfolio | 3.2m $517.6m | Reduced -15.4k |
| FMR LLC 0.03% of their portfolio | 3.2m $511.1m | Reduced -244.9k |
| PRICE T ROWE ASSOCIATES INC /MD/ 0.05% of their portfolio | 2.8m $440.1m | Reduced -879.2k |
| VICTORY CAPITAL MANAGEMENT INC 0.23% of their portfolio | 2.6m $409.5m | Reduced -1.0m |
| WELLINGTON MANAGEMENT GROUP LLP 0.07% of their portfolio | 2.6m $407.8m | Reduced -461.8k |
| STATE STREET CORP 0.01% of their portfolio | 2.0m $322.4m | Reduced -26.4k |
| JPMORGAN CHASE & CO 0.02% of their portfolio | 1.6m $247.9m | Added +222.3k |
| NEUBERGER BERMAN GROUP LLC 0.17% of their portfolio | 1.5m $233.5m | Reduced -173.6k |
| GEODE CAPITAL MANAGEMENT, LLC 0.01% of their portfolio | 1.3m $200.4m | Added +5.6k |
| DIMENSIONAL FUND ADVISORS LP 0.04% of their portfolio | 1.1m $178.6m | Reduced -147.9k |
| FRANKLIN RESOURCES INC 0.04% of their portfolio | 1.0m $166.5m | Reduced -367.2k |
| COOKE & BIELER LP 1.61% of their portfolio | 966.7k $154.5m | Reduced -355.2k |
| NORGES BANK 0.02% of their portfolio | 922.7k $147.5m | Not comparable |
| Madison Asset Management, LLC 1.69% of their portfolio | 921.5k $147.2m | Reduced -54.6k |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC 0.02% of their portfolio | 870.7k $139.1m | Added +24.3k |
| WESTFIELD CAPITAL MANAGEMENT CO LP 0.56% of their portfolio | 839.8k $134.2m | Added +516.4k |
| MILLENNIUM MANAGEMENT LLC 0.09% of their portfolio | 817.3k $130.6m | Added +371.0k |
| Bank of New York Mellon Corp 0.02% of their portfolio | 788.6k $126.0m | Added +137.5k |
| PRINCIPAL FINANCIAL GROUP INC 0.06% of their portfolio | 765.6k $122.4m | Reduced -53.2k |
| Point72 Asset Management, L.P. 0.16% of their portfolio | 625.8k $100.0m | Reduced -387.8k |
| ROYCE & ASSOCIATES LP 1.00% of their portfolio | 616.6k $98.5m | Reduced -210.5k |
| MANUFACTURERS LIFE INSURANCE COMPANY, THE 0.08% of their portfolio | 606.2k $96.9m | Reduced -217.0k |
| Southpoint Capital Advisors LP 2.23% of their portfolio | 600.0k $95.9m | New |
| NORDEA INVESTMENT MANAGEMENT AB 0.08% of their portfolio | 599.8k $96.6m | Reduced -996.6k |
| MORGAN STANLEY 0.01% of their portfolio | 590.5k $94.4m | Reduced -62.1k |
| NORTHERN TRUST CORP 0.01% of their portfolio | 566.0k $90.4m | Reduced -25.9k |
| FRONTIER CAPITAL MANAGEMENT CO LLC 0.93% of their portfolio | 550.7k $88.0m | Reduced -530.0k |
| Channing Capital Management, LLC 2.18% of their portfolio | 531.2k $84.9m | Reduced -213.0k |
| NATIXIS ADVISORS, LLC 0.12% of their portfolio | 522.4k $83.5m | Added +41.2k |
| Balyasny Asset Management L.P. 0.15% of their portfolio | 511.6k $81.8m | Reduced -338.6k |
| BANK OF AMERICA CORP /DE/ 0.01% of their portfolio | 480.2k $76.7m | Added +52.2k |
| CITADEL ADVISORS LLC 0.05% of their portfolio | 457.9k $73.2m | Added +316.7k |
| Blue Grotto Capital, LLC 6.82% of their portfolio | 415.5k $66.4m | Added +203.7k |
| AMERICAN CENTURY COMPANIES INC 0.03% of their portfolio | 397.6k $63.5m | Added +395.4k |
| WELLS FARGO & COMPANY/MN 0.01% of their portfolio | 391.2k $62.5m | Added +32.5k |
| JANE STREET GROUP, LLC 0.07% of their portfolio | 383.1k $61.2m | Added +251.5k |
| SUMMIT PARTNERS PUBLIC ASSET MANAGEMENT, LLC 1.71% of their portfolio | 381.5k $61.0m | Reduced -214.6k |
| NOMURA HOLDINGS INC 0.17% of their portfolio | 364.0k $58.2m | Reduced -62.5k |
| Nuveen, LLC 0.01% of their portfolio | 341.4k $54.6m | Added +60.2k |
| BARCLAYS PLC 0.02% of their portfolio | 340.3k $54.4m | Reduced -26.8k |
| Delta Global Management LP 3.81% of their portfolio | 327.4k $52.3m | Added +175.9k |
| UBS Group AG 0.01% of their portfolio | 323.7k $51.7m | Reduced -330.1k |
| ROYAL BANK OF CANADA 0.01% of their portfolio | 309.8k $49.5m | Reduced -370.0k |
| VALUE HOLDINGS MANAGEMENT CO. LLC 7.96% of their portfolio | 297.7k $47.6m | Unchanged |
| Harvey Partners, LLC 4.15% of their portfolio | 289.2k $46.2m | Added +197 |
| Park West Asset Management LLC 3.75% of their portfolio | 278.6k $44.5m | Added +218.6k |
| Polaris Capital Management, LLC 3.51% of their portfolio | 265.1k $42.4m | Reduced -136.2k |
| SYSTEMATIC FINANCIAL MANAGEMENT LP 1.00% of their portfolio | 264.7k $42.3m | Reduced -712 |
| RAYMOND JAMES FINANCIAL INC 0.01% of their portfolio | 249.3k $40.0m | Added +72.1k |
| Penserra Capital Management LLC 0.45% of their portfolio | 237.9k $38.0m | Reduced -58.1k |
| Defiance ETFs, LLC 1.26% of their portfolio | 237.9k $38.5m | First filing |
| Quantinno Capital Management LP 0.07% of their portfolio | 230.9k $36.9m | Added +71.7k |
| CRAMER ROSENTHAL MCGLYNN LLC 2.38% of their portfolio | 230.7k $36.9m | New |
| Gotham Asset Management, LLC 0.13% of their portfolio | 225.2k $36.0m | Added +26.1k |
| SummitTX Capital, L.P. 1.00% of their portfolio | 205.8k $32.9m | Added +9.0k |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC 0.01% of their portfolio | 200.2k $32.0m | Reduced -6.3k |
| AQR CAPITAL MANAGEMENT LLC 0.02% of their portfolio | 196.7k $31.4m | Added +26.7k |
| Ceredex Value Advisors LLC 0.90% of their portfolio | 186.5k $29.8m | Reduced -13.6k |
| LOOMIS SAYLES & CO L P 0.04% of their portfolio | 184.2k $29.4m | Reduced -27.4k |
| GOLDMAN SACHS GROUP INC 0.00% of their portfolio | 180.0k $28.8m | Reduced -36.3k |
| RHUMBLINE ADVISERS 0.02% of their portfolio | 176.0k $28.1m | Reduced -7.4k |
| Mizuho Markets Cayman LP 1.41% of their portfolio | 175.0k $28.0m | New |
| BANK OF MONTREAL /CAN/ 0.01% of their portfolio | 164.8k $26.3m | Added +56.5k |
| BNP PARIBAS FINANCIAL MARKETS 0.02% of their portfolio | 160.6k $25.7m | Added +91.9k |
| Handelsbanken Fonder AB 0.08% of their portfolio | 158.4k $25.3m | Added +48.8k |
| BESSEMER GROUP INC 0.04% of their portfolio | 158.0k $25.3m | Reduced -54.0k |
| Retirement Systems of Alabama 0.08% of their portfolio | 156.7k $25.0m | Reduced -585 |
| SILVERCREST ASSET MANAGEMENT GROUP LLC 0.17% of their portfolio | 156.6k $25.0m | Reduced -14.5k |
| NEW YORK STATE COMMON RETIREMENT FUND 0.03% of their portfolio | 151.3k $24.2m | Reduced -71.7k |
| NOMURA ASSET MANAGEMENT INTERNATIONAL INC. 0.04% of their portfolio | 150.7k $24.1m | First filing |
| Corient Private Wealth LP 0.00% of their portfolio | 144.9k $5.3m | Added +139.0k |
| KENNEDY CAPITAL MANAGEMENT LLC 0.49% of their portfolio | 144.1k $23.0m | Reduced -27.4k |
| Polar Capital Holdings Plc 0.10% of their portfolio | 143.5k $22.9m | Reduced -1.1k |
| AMERIPRISE FINANCIAL INC 0.01% of their portfolio | 142.5k $22.8m | Reduced -38.0k |
| Amundi 0.01% of their portfolio | 140.2k $22.4m | Added +38.0k |
| DEUTSCHE BANK AG\ 0.01% of their portfolio | 134.0k $21.4m | Reduced -210 |
| Swiss National Bank 0.01% of their portfolio | 132.5k $21.2m | Added +2.5k |
| NEEDHAM INVESTMENT MANAGEMENT LLC 1.32% of their portfolio | 130.5k $20.9m | Reduced -250 |
| Jain Global LLC 0.20% of their portfolio | 127.0k $20.3m | Reduced -6.2k |
| SEI INVESTMENTS CO 0.02% of their portfolio | 126.1k $20.1m | Added +13.9k |
| California Public Employees Retirement System 0.01% of their portfolio | 114.4k $18.3m | Reduced -47 |
| TUDOR INVESTMENT CORP ET AL 0.09% of their portfolio | 104.5k $16.7m | New |
| Concentric Capital Strategies, LP 0.85% of their portfolio | 102.6k $16.4m | Added +27.7k |
| Legal & General Group Plc 0.00% of their portfolio | 99.6k $15.9m | Reduced -3.8k |
| FEDERATED HERMES, INC. 0.03% of their portfolio | 99.3k $15.9m | Reduced -615 |
| ENVESTNET ASSET MANAGEMENT INC 0.00% of their portfolio | 93.2k $14.9m | Reduced -8.6k |
| Assenagon Asset Management S.A. 0.02% of their portfolio | 92.9k $14.8m | New |
| SHAPIRO CAPITAL MANAGEMENT LLC 0.75% of their portfolio | 89.3k $14.3m | Reduced -219.7k |
| Thrivent Financial for Lutherans 0.02% of their portfolio | 87.6k $14.0m | Reduced -17.5k |
| ALLIANCEBERNSTEIN L.P. 0.00% of their portfolio | 86.1k $13.8m | Added +1.4k |
| NFJ INVESTMENT GROUP, LLC 0.49% of their portfolio | 85.6k $13.7m | Reduced -16.1k |
| STRS OHIO 0.05% of their portfolio | 80.8k $12.9m | Added +7.2k |
| Divisar Capital Management LLC 3.48% of their portfolio | 77.5k $12.4m | Added +15.5k |
| GLENVIEW CAPITAL MANAGEMENT, LLC 0.25% of their portfolio | 74.2k $11.9m | Reduced -97.7k |
| Phocas Financial Corp. 1.52% of their portfolio | 73.4k $11.7m | Reduced -177 |
| BANK OF NOVA SCOTIA 0.02% of their portfolio | 72.2k $11.5m | New |
| AGF MANAGEMENT LTD 0.05% of their portfolio | 69.7k $11.1m | New |