In 1984, the Department of Justice settled its antitrust case against AT&T. The agreement, embedded in the Modification of Final Judgment, led to a divestiture of the local telephone exchanges from AT&T to the Regional Bell Operating Companies (known as the Baby Bells ). This agreement gave unprecedented power over a major US industry to one man, Judge Harold Greene of the US District Court of the District of Columbia. The Baby Bells could not enter any line of business without approval from Judge Greene. With technological change it became increasingly desirable for the Baby Bells to enter different lines of business, but each attempt was subject to legal challenge and lengthy, costly litigation. In 1994, the Baby Bells mounted a major legal challenge to the Modification of Final Judgement (MFJ).