Patterson Companies, Inc. (Patterson) is a distributor serving three markets: the United States companion animal (dogs, cats and other common household pets) and equine veterinary supply, and the worldwide rehabilitation and assistive products supply market. The Company operates in three segments: dental supply, veterinary supply and rehabilitation supply. As Patterson's business, Patterson Dental is a distributor of dental products in North America. Webster Veterinary (Webster) is a distributor of veterinary supplies primarily to companion-pet (dogs, cats and other common household pets) and equine veterinary clinics across the United States. Effective August 2, 2013, it acquired Mercer Mastery, a developer of dental practice software, from Lovell Minnick Partners LLC's Mercer Advisors Inc subsidiary. In August 2013, Patterson Companies Inc completed acquisition of the stock of National Veterinary Services Limited, a wholly owned subsidiary of Dechra Pharmaceuticals PLC.