Welcome to our dedicated page for MKS SEC filings (Ticker: MKSI), a comprehensive resource for investors and traders seeking official regulatory documents including 10-K annual reports, 10-Q quarterly earnings, 8-K material events, and insider trading forms.
MKS Inc. SEC filings document operating results, capital-structure activity and governance matters for a Nasdaq-listed provider of technology solutions for semiconductor manufacturing, electronics and packaging, and specialty industrial applications. Form 8-K reports disclose results of operations and financial condition, financial guidance updates, material definitive agreements, debt refinancing activity, senior notes, credit facilities and registered common stock information.
The company’s proxy materials cover board and shareholder voting matters, executive compensation and related governance disclosures. Other current reports address officer transitions and compensation arrangements, providing formal records of management, governance and financing developments tied to MKS’s public-company structure.
MKS Inc director Joseph B. Donahue reported an open‑market sale of 2,100 shares of Common Stock on May 27, 2026 at a weighted average price of $327.954 per share.
The sale was executed in multiple trades between $327.90 and $328.21. After this transaction, Donahue directly holds about 10,032.704 MKS Inc common shares.
MKS Inc director Gerald G. Colella reported a net sale of 20,000 shares of MKS Inc common stock through an affiliated trust. On May 27, 2026, The Gerald G. Colella 2019 Trust executed seven open‑market sales at prices around $330 per share, leaving the trust holding 39,553 shares afterward.
Separately, Colella is shown with 8,998.886 shares held directly as a position entry rather than a new trade. A footnote states that at least one of the sales was made under a pre‑arranged Rule 10b5‑1 trading plan adopted on February 24, 2026, indicating the transactions were scheduled in advance.
MKS Inc executive Henry David Philip reported an open-market sale of 2,500 shares of Common Stock at $330.50 per share. After the transaction, he directly holds 16,341.368 shares. The sale was carried out under a pre-arranged Rule 10b5-1 trading plan adopted on February 24, 2026.
MKS Inc. trustee filed a Form 144 notice to sell 20,000 shares of Common Stock. The filing lists the securities as a stock grant dated 02/15/2019 and the sale method as cashless. The excerpt shows two reported dispositions of 10,000 shares each on 02/20/2026 and 02/24/2026 with proceeds of 2528997.85 and 2539674.98 respectively.
MKS INC EVP & CFO Mayampurath Ramakumar sold 8,810 shares of Common Stock in an open-market transaction. The sale took place on May 22, 2026 at an average price of $315.4800 per share.
After this transaction, he directly owned 1.1390 shares of MKS INC common stock, according to the filing. The sale was carried out under a pre-arranged Rule 10b5-1 trading plan adopted on February 20, 2026, indicating it was scheduled in advance rather than timed discretionarily.
MKS Inc President & CEO John Tseng-Chung Lee sold 10,000 shares of MKS Inc common stock in an open-market transaction at a price of $315.48 per share. The sale was made under a pre-arranged Rule 10b5-1 trading plan adopted by the executive.
After this transaction, Lee still directly holds about 144,696 shares of MKS Inc common stock, indicating he retains a substantial equity stake in the company despite the sale.
Fidelity Brokerage Services LLC submitted a Form 144 notice to sell 10,000 shares of Common Stock of the issuer listed on NASDAQ. The filing shows a proposed sale date of 05/22/2026 and lists two restricted‑stock vesting lots of 2,659 and 7,341 shares dated 02/15/2021 and 02/15/2026.
MKSI: Notice of proposed sale under Section 144 related to recently vested restricted shares
The filing lists restricted stock vesting entries for 3,143 shares on 02/15/2026 and 5,667 shares on 11/15/2025
The filing shows a broker entry for Fidelity Brokerage Services LLC and a date of 05/22/2026. The document records securities to be sold associated with compensation vesting; timing and exact sale mechanics are not detailed in the excerpt.