PERTH, Australia – Australia's Sonic Healthcare Ltd. is significantly expanding its U.S. footprint with the acquisition of Aurora Diagnostics LLC, of Palm Beach Gardens, Fla., for A$750 million (US$540 million) in an all-cash deal. About 90 percent of Aurora's revenue comes from its anatomical pathology services, and Sonic has deep roots in the anatomical pathology market. The acquisition extends Sonic's existing presence in anatomical pathology, which is a fragmented market in the U.S.