Pall Corporation sees no merit in an action filed by Entegris alleging infringement of a U.S. patent just issued on April 4, 2006. This is a continuation of ongoing litigation between the two parties. The claims of the new patent were apparently crafted in an effort to circumvent a January 12, 2005 U.S. District Court ruling that the claims of Entegris' earlier patents are likely to be invalid over earlier developments--a determination that led to the dissolution of an injunction that the Court had previously entered. On March 21, 2006 the European Patent Office revoked Entegris' related European Patent 0 818 228. The claims of the revoked patent are very similar to those in Entegris' new U.S. patent. Pall will ask the U.S. Court to reach the same conclusion as that of the European Patent Office and find the U.S. patent to be invalid. Pall intends to vigorously defend its right to provide its customers with state-of-the art photolithography filtration technologies. The Entegris patent is not directed to filtration technologies; but is directed to a specific manifold assembly that connects fluid separation devices to fluid processing systems. Pall feels that this suit is an attempt to overcome the superiority of Pall filtration products in the highly demanding photolithography field.