🟢 MKS Instruments is trading 18.78% up in after-hours trading with no confirmed company-specific catalyst

MKS Instruments is trading at $321.29, +18.78% after-hours after closing at $270.48 on August 25, 2026, with no confirmed company-specific announcement explaining the surge.

• The latest major report was August 5 earnings; the Nasdaq Composite was up 0.60%, which does not fully explain the move.
• Mizuho maintained Outperform while lowering its target to $330 from $360 on August 25.