Mks Instruments Inc (MKSI): Congress and insider trades
Who in Congress and inside the company traded MKSI, when each filing appeared, and what buying after each one would have earned against the S&P 500.
Key Facts
- Mks Instruments Inc (MKSI) is a listed stock on NASDAQ.
- 2 members of Congress filed 9 buys and 7 sells of MKSI, the latest published 2025-05-15 (15 May 2025).
- Insiders filed 0 open market buys worth $0 and 12 sells worth $21M, the latest filed 2026-09-02 (2 September 2026).
- Across 2 scored buys, Congress averaged +1.3% against the S&P 500 (SPY) over the 90 days after disclosure, with 50% of them ahead of the index. That result is too few trades to draw a conclusion.
- Data as of 2026-09-29 (29 September 2026).
Congress trades in MKSI
as of 2025-05-15| Filed | Member | Type | Size | Days to file | 90 day vs S&P |
|---|---|---|---|---|---|
| 15 May 2025 | Ro Khanna (D-CA) | sell | 15K–50K | 27 | n/a |
| 15 May 2025 | Ro Khanna (D-CA) | sell | 1K–15K | 27 | n/a |
| 15 May 2025 | Ro Khanna (D-CA) | buy | 1K–15K | 34 | +7.0% |
| 15 May 2025 | Ro Khanna (D-CA) | sell | 1K–15K | 26 | n/a |
| 15 May 2025 | Ro Khanna (D-CA) | buy | 1K–15K | 32 | +7.0% |
| 15 May 2025 | Ro Khanna (D-CA) | buy | 1K–15K | 22 | +7.0% |
| 15 May 2025 | Ro Khanna (D-CA) | buy | 1K–15K | 38 | +7.0% |
| 15 May 2025 | Ro Khanna (D-CA) | buy | 1K–15K | 38 | +7.0% |
| 15 May 2025 | Ro Khanna (D-CA) | sell | 1K–15K | 27 | n/a |
| 15 May 2025 | Ro Khanna (D-CA) | buy | 1K–15K | 39 | +7.0% |
| 15 May 2025 | Ro Khanna (D-CA) | sell | 1K–15K | 26 | n/a |
| 15 May 2025 | Ro Khanna (D-CA) | buy | 15K–50K | 39 | +7.0% |
| 15 May 2025 | Ro Khanna (D-CA) | buy | 1K–15K | 34 | +7.0% |
| 15 May 2025 | Ro Khanna (D-CA) | sell | 1K–15K | 25 | n/a |
| 12 May 2023 | Tommy Tuberville (R-AL) | sell | 1K–15K | 39 | n/a |
| 8 Apr 2022 | Tommy Tuberville (R-AL) | buy | 1K–15K | 9 | -4.4% |
Nothing matches that search.
Insider trades in MKSI
as of 2026-09-02| Filed | Insider | Type | Shares | Price | Value | 90 day vs S&P |
|---|---|---|---|---|---|---|
| 2 Sep 2026 | Mora Elizabeth | sell | 300 | $250.96 | $75.3K | n/a |
| 17 Aug 2026 | Lee John Tseng-Chung | sell | 10,000 | $302.01 | $3.0M | n/a |
| 4 Aug 2026 | Williams John Edward | sell | 457 | $288.31 | $132K | n/a |
| 16 Jun 2026 | Schreiner James Alan | sell | 3,500 | $345.82 | $1.2M | n/a |
| 11 Jun 2026 | Schreiner James Alan | sell | 781 | $317.42 | $248K | n/a |
| 2 Jun 2026 | Mora Elizabeth | sell | 300 | $318.02 | $95.4K | n/a |
| 2 Jun 2026 | Henry David Philip | sell | 6,000 | $314.43 | $1.9M | n/a |
| 28 May 2026 | COLELLA GERALD G | sell | 20,000 | $333.40 | $6.7M | n/a |
| 28 May 2026 | Donahue Joseph B | sell | 2,100 | $327.95 | $689K | n/a |
| 27 May 2026 | Henry David Philip | sell | 2,500 | $330.50 | $826K | n/a |
| 26 May 2026 | Lee John Tseng-Chung | sell | 10,000 | $315.48 | $3.2M | n/a |
| 26 May 2026 | Mayampurath Ramakumar | sell | 8,810 | $315.48 | $2.8M | n/a |
Nothing matches that search.
Related pages
Frequently asked questions
Who has bought MKSI?
9 Congress buys by 2 members and 0 insider buys are on file. The tables on this page list every one.
Did buying MKSI after a disclosure beat the market?
Across 2 scored buys, Congress averaged +1.3% against the S&P 500 (SPY) over the 90 days after disclosure, with 50% of them ahead of the index. That result is too few trades to draw a conclusion. A single stock is a small sample.
Sources: Congressional trades: STOCK Act disclosures, collected from CapitolTrades. Insider trades: SEC Form 4 filings, collected from Finviz. Prices: Yahoo Finance daily adjusted closes. Data as of 2026-09-29 (29 September 2026). About these sources.
Not investment advice. Past disclosed trades do not predict future returns. Disclosures are published late, so the trades shown are ones you could only have copied after the fact. Talk to a licensed adviser before you invest.