He has led Parsons’ teams in various bench and jury trials and has represented clients in numerous appeals before the U.S. Court of Appeals for the Federal Circuit. He is recognized for Intellectual Property Litigation in Chambers USA ®, Best Lawyers in America ® , Managing Intellectual Property "IP Stars" ®, and IAM Patent 1000, The World's Leading Patent Professionals ®. Benchmark Litigation ® lists Mr. Mangum as one of 18 "Utah Litigation Stars" and wrote that "David Mangum is one of the, if not the best Intellectual Property litigators, certainly in the region."