🟢 MKS Instruments is trading 20.49% up in after-hours trading with no clear company-specific catalyst identified

MKS Instruments is trading at $260.37, up 20.49% after the October 21 regular-session close; no clear company-specific catalyst was identified.

• The broader semiconductor sector was higher after hours, with SOXX up 2.61%, but that rally does not explain MKS Instruments’ larger move.
• The Ophir Optics sale was announced October 19, making it prior news; MKS’s investor-relations listings show no October 21 release.