Burke Kathleen Flaherty, EVP, GC and Secretary of MKS Instruments ($MKSI), sold shares once on the open market in the last year, totaling $1.1 million. Her most recent sale occurred on February 20, 2026. These sales rank 4,775th among 11,678 individual insiders, below the average of $8.6 million per seller and 6.4 transactions. She made no open market purchases during this period.
| Transaction Date | Company | Ticker | Insider Name | Title | Transaction Type | Security | Shares | Price | Shares Owned Following | Total Shares Outstanding | % of Owned | % of Outstanding |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Feb. 20, 2026 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | S | Common Stock | 4254 | $250.00 | 53,794.4850 | 67,600,000 | 7.33% | 0.01% |
| Feb. 17, 2026 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Common Stock | 3451 | $0.00 | 54,611.0080 | 67,600,000 | 6.75% | 0.01% |
| Feb. 17, 2026 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Common Stock | 1788 | $0.00 | 56,398.7430 | 67,600,000 | 3.27% | 0.00% |
| Feb. 17, 2026 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Restricted Stock Unit | 2493 | $0.00 | 15,128.9860 | 67,600,000 | 14.15% | 0.00% |
| Feb. 17, 2026 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Restricted Stock Unit | 2336 | $0.00 | 17,621.9860 | 67,600,000 | 11.70% | 0.00% |
| Feb. 17, 2026 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Restricted Stock Unit | 1576 | $0.00 | 19,957.9860 | 67,600,000 | 7.32% | 0.00% |
| Feb. 17, 2026 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Restricted Stock Unit | 563 | $0.00 | 21,533.9860 | 67,600,000 | 2.55% | 0.00% |
| Feb. 17, 2026 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Restricted Stock Unit | 1788 | $0.00 | 22,096.5260 | 67,600,000 | 7.48% | 0.00% |
| Feb. 17, 2026 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Restricted Stock Unit | 3451 | $0.00 | 23,884.2610 | 67,600,000 | 12.62% | 0.01% |
| Feb. 17, 2026 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | A | Restricted Stock Unit | 3328 | $0.00 | 27,335.1200 | 67,600,000 | 13.86% | 0.00% |
| Feb. 17, 2026 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | F | Common Stock | 5318 | $260.74 | 58,048.4850 | 67,600,000 | 8.39% | 0.01% |
| Feb. 17, 2026 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Common Stock | 2493 | $0.00 | 63,366.2830 | 67,600,000 | 4.10% | 0.00% |
| Feb. 17, 2026 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Common Stock | 2336 | $0.00 | 60,873.2830 | 67,600,000 | 3.99% | 0.00% |
| Feb. 17, 2026 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Common Stock | 1576 | $0.00 | 58,537.2830 | 67,600,000 | 2.77% | 0.00% |
| Feb. 17, 2026 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Common Stock | 563 | $0.00 | 56,961.2830 | 67,600,000 | 1.00% | 0.00% |
| Feb. 8, 2026 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | A | Restricted Stock Unit | 7009 | $0.00 | 24,007.3650 | 67,600,000 | 41.23% | 0.01% |
| Oct. 31, 2025 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Common Stock | 158 | $0.00 | 51,232.5090 | 67,600,000 | 0.31% | 0.00% |
| Oct. 31, 2025 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Common Stock | 52 | $0.00 | 51,284.5090 | 67,600,000 | 0.10% | 0.00% |
| Oct. 31, 2025 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Common Stock | 82 | $0.00 | 51,366.5090 | 67,600,000 | 0.16% | 0.00% |
| Oct. 31, 2025 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Common Stock | 144 | $0.00 | 51,510.5090 | 67,600,000 | 0.28% | 0.00% |
| Oct. 31, 2025 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Common Stock | 341 | $0.00 | 51,851.5090 | 67,600,000 | 0.66% | 0.00% |
| Oct. 31, 2025 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Restricted Stock Unit | 341 | $0.00 | 16,998.7370 | 67,600,000 | 1.97% | 0.00% |
| Oct. 31, 2025 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Restricted Stock Unit | 158 | $0.00 | 17,617.7370 | 67,600,000 | 0.89% | 0.00% |
| Oct. 31, 2025 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Restricted Stock Unit | 52 | $0.00 | 17,565.7370 | 67,600,000 | 0.30% | 0.00% |
| Oct. 31, 2025 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Restricted Stock Unit | 82 | $0.00 | 17,483.7370 | 67,600,000 | 0.47% | 0.00% |
| Oct. 31, 2025 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Restricted Stock Unit | 144 | $0.00 | 17,339.7370 | 67,600,000 | 0.82% | 0.00% |
| Oct. 31, 2025 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | F | Common Stock | 777 | $143.71 | 51,074.5090 | 67,600,000 | 1.50% | 0.00% |
| Feb. 18, 2025 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Common Stock | 2287 | $0.00 | 45,533.3160 | 67,600,000 | 5.29% | 0.00% |
| Feb. 18, 2025 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Common Stock | 1645 | $0.00 | 47,178.3920 | 67,600,000 | 3.61% | 0.00% |
| Feb. 18, 2025 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Common Stock | 3608 | $0.00 | 50,786.3920 | 67,600,000 | 7.65% | 0.01% |
| Feb. 18, 2025 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Common Stock | 1870 | $0.00 | 52,656.3920 | 67,600,000 | 3.68% | 0.00% |
| Feb. 18, 2025 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Common Stock | 588 | $0.00 | 53,244.4220 | 67,600,000 | 1.12% | 0.00% |
| Feb. 18, 2025 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Common Stock | 1648 | $0.00 | 54,892.4220 | 67,600,000 | 3.10% | 0.00% |
| Feb. 18, 2025 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | F | Common Stock | 3970 | $103.67 | 50,922.4220 | 67,600,000 | 7.23% | 0.01% |
| Feb. 18, 2025 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | A | Restricted Stock Unit | 7822 | $0.00 | 29,421.5990 | 67,600,000 | 36.21% | 0.01% |
| Feb. 18, 2025 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Restricted Stock Unit | 2287 | $0.00 | 27,134.8430 | 67,600,000 | 7.77% | 0.00% |
| Feb. 18, 2025 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Restricted Stock Unit | 1645 | $0.00 | 25,489.7670 | 67,600,000 | 6.06% | 0.00% |
| Feb. 18, 2025 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Restricted Stock Unit | 3608 | $0.00 | 21,881.7670 | 67,600,000 | 14.15% | 0.01% |
| Feb. 18, 2025 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Restricted Stock Unit | 1870 | $0.00 | 20,011.7670 | 67,600,000 | 8.55% | 0.00% |
| Feb. 18, 2025 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Restricted Stock Unit | 588 | $0.00 | 19,423.7370 | 67,600,000 | 2.94% | 0.00% |
| Feb. 18, 2025 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Restricted Stock Unit | 1648 | $0.00 | 17,775.7370 | 67,600,000 | 8.48% | 0.00% |
| Feb. 10, 2025 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | A | Restricted Stock Unit | 1766 | $0.00 | 21,599.4690 | 67,600,000 | 8.90% | 0.00% |
| March 1, 2024 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | S | Common Stock | 7411 | $122.89 | 42,999.0210 | 66,800,000 | 14.70% | 0.01% |
| Feb. 15, 2024 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Common Stock | 1017 | $0.00 | 45,913.0210 | 66,800,000 | 2.26% | 0.00% |
| Feb. 15, 2024 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Common Stock | 2287 | $0.00 | 48,200.0210 | 66,800,000 | 4.98% | 0.00% |
| Feb. 15, 2024 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Common Stock | 1645 | $0.00 | 49,845.0210 | 66,800,000 | 3.41% | 0.00% |
| Feb. 15, 2024 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Common Stock | 3608 | $0.00 | 53,453.0210 | 66,800,000 | 7.24% | 0.01% |
| Feb. 15, 2024 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Common Stock | 1869 | $0.00 | 55,322.0210 | 66,800,000 | 3.50% | 0.00% |
| Feb. 15, 2024 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | F | Common Stock | 4912 | $122.15 | 50,410.0210 | 66,800,000 | 8.88% | 0.01% |
| Feb. 15, 2024 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | A | Restricted Stock Unit | 4945 | $0.00 | 32,292.2670 | 66,800,000 | 18.08% | 0.01% |
| Feb. 15, 2024 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Restricted Stock Unit | 2033 | $0.00 | 30,259.7060 | 66,800,000 | 6.29% | 0.00% |
| Feb. 15, 2024 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Restricted Stock Unit | 1017 | $0.00 | 29,242.9260 | 66,800,000 | 3.36% | 0.00% |
| Feb. 15, 2024 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Restricted Stock Unit | 2287 | $0.00 | 26,955.9260 | 66,800,000 | 7.82% | 0.00% |
| Feb. 15, 2024 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Restricted Stock Unit | 1645 | $0.00 | 25,310.9260 | 66,800,000 | 6.10% | 0.00% |
| Feb. 15, 2024 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Restricted Stock Unit | 1869 | $0.00 | 19,833.9260 | 66,800,000 | 8.61% | 0.00% |
| Feb. 15, 2024 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Restricted Stock Unit | 3608 | $0.00 | 21,702.9260 | 66,800,000 | 14.25% | 0.01% |
| Feb. 15, 2024 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Common Stock | 2033 | $0.00 | 44,896.2410 | 66,800,000 | 4.74% | 0.00% |
| Feb. 5, 2024 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | A | Restricted Stock Unit | 10825 | $0.00 | 27,346.7680 | 66,800,000 | 65.52% | 0.02% |
| Aug. 7, 2023 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | S | Common Stock | 6186 | $101.08 | 48,114.6750 | 59,900,000 | 11.39% | 0.01% |
| Aug. 7, 2023 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | S | Common Stock | 5377 | $101.40 | 42,737.6080 | 59,900,000 | 11.18% | 0.01% |
| Feb. 15, 2023 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Restricted Stock Unit | 2286 | $0.00 | 18,166.9090 | 59,900,000 | 11.18% | 0.00% |
| Feb. 15, 2023 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Restricted Stock Unit | 1016 | $0.00 | 20,452.9090 | 59,900,000 | 4.73% | 0.00% |
| Feb. 15, 2023 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Restricted Stock Unit | 2033 | $0.00 | 21,468.9090 | 59,900,000 | 8.65% | 0.00% |
| Feb. 15, 2023 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Restricted Stock Unit | 1281 | $0.00 | 23,501.9090 | 59,900,000 | 5.17% | 0.00% |
| Feb. 15, 2023 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Restricted Stock Unit | 1845 | $0.00 | 24,783.0100 | 59,900,000 | 6.93% | 0.00% |
| Feb. 15, 2023 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | A | Restricted Stock Unit | 5609 | $0.00 | 26,627.6350 | 59,900,000 | 26.68% | 0.01% |
| Feb. 15, 2023 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Common Stock | 1645 | $0.00 | 57,624.5790 | 59,900,000 | 2.94% | 0.00% |
| Feb. 15, 2023 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Common Stock | 2286 | $0.00 | 55,979.5790 | 59,900,000 | 4.26% | 0.00% |
| Feb. 15, 2023 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Common Stock | 1016 | $0.00 | 53,693.5790 | 59,900,000 | 1.93% | 0.00% |
| Feb. 15, 2023 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Common Stock | 2033 | $0.00 | 52,677.5790 | 59,900,000 | 4.01% | 0.00% |
| Feb. 15, 2023 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Common Stock | 1281 | $0.00 | 50,644.5790 | 59,900,000 | 2.60% | 0.00% |
| Feb. 15, 2023 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Common Stock | 1845 | $0.00 | 49,363.4780 | 59,900,000 | 3.88% | 0.00% |
| Feb. 15, 2023 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | F | Common Stock | 3474 | $100.29 | 54,150.5790 | 59,900,000 | 6.03% | 0.01% |
| Feb. 15, 2023 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | M | Restricted Stock Unit | 1645 | $0.00 | 16,521.9090 | 59,900,000 | 9.05% | 0.00% |
| Feb. 8, 2023 | MKS INC | $MKSI | Burke Kathleen Flaherty | EVP, GC & Secretary | A | Restricted Stock Unit | 6860 | $0.00 | 21,018.9000 | 59,900,000 | 48.45% | 0.01% |