sentences:  Zeglis began his career in 1973 in Chicago, Illinois as an associate at the law firm now known as Sidley Austin.He became an official partner five years later in 1978.While there, he worked on the defense of the AT&T account during the antitrust lawsuit United States v. AT&T, and when the case resulted in the breakup of the AT&T/Bell System, he helped restructure the system.