In his practice as an Orange County attorney, William D. Chapman, serves as an intellectual property attorney representing both plaintiffs and defendants.  He has handled substantial patent and copyright litigation, with damages at issue in the millions of dollars. 

In one case, he represented a water bed manufacturer in defending a patent infringement suit by a major water bed manufacturer.  He assisted in defending a companion case at trial which ended in a successful defense verdict.  In another case, he represented a copyright holder in a major copyright infringement suit which was resolved by way of settlement prior to trial.