Vista-based Aperio Technologies, which develops digital pathology products for the healthcare and life sciences industries, is reporting that it has filed a patent infringement lawsuit against Olympus America, Inc., Hamamatsu Corporation and Hamamatsu Photonics KK. According to Aperio, it alleges that Hamamatsu's digital pathology system, marketed under the name NanoZoomer, infringes on three of the firm's U.S. patents. Olympus America is the distributor for the product. Aperio said that the lawsuits came after "years of repeated and unsuccessful attempts to engage Olympus America and Hamamatsu in discussions" over the infringement. Aperio said it has hired litigator Quinn Emanuel Urquhart Oliver & Hedges, LLP in the lawsuit.