April 17 2008 Disclosure of Equity Participation Pursuant to the Swiss Stock Exchange Act

Syracuse, New York / Zurich, Switzerland — April 17, 2008 — INFICON Holding AG (SWX Swiss Exchange: IFCN), a leading, worldwide manufacturer of instrumentation and process control software for advanced industrial vacuum processes, today announced, that Corisol Holding AG, Blegistrasse 15, 6340 Baar (contact person Beat Frey, +41 41 760 3026) disclosed on April 14, 2008, that it held 125'144 registered shares of INFICON Holding AG at CHF 5 par value each since a purchase on April 10, 2008. This represents 5.26% of the voting rights in INFICON Holding AG. Beat Frey, 8142 Uitikon-Waldegg, is the economic beneficiary of Corisol Holding AG.