May 2 2006 Disclosure of Equity Participations Pursuant to the Swiss Stock Exchange Act

Syracuse, New York/Zurich, Switzerland — May 2, 2006— INFICON Holding AG (SWX Swiss Exchange and NASDAQ: IFCN), a leading manufacturer of vacuum instrumentation and process control software for the semiconductor and related industries and other industrial applications, today announced that according to a notification received on April 28, 2006 from Bank Julius Baer & Co. Ltd, Bahnhofstrasse 36, 8010 Zürich, the bank's holdings in INFICON Holding AG fell below the 5% threshold of the voting rights on April 24, 2006.

CONTACT: INFICON
Betty Ann Kram, +1-315-434-1122
BettyAnn.Kram@inficon.com
or
European Contact
sensus pr GmbH
Bernhard Schweizer, +41-43-366-5511
bschweizer@sensus.ch

SOURCE: INFICON