OCC Definition

Office of the Comptroller of the Currency.
American Heritage
Webster's New World Finance

The term applied in the United States prior to the breakup of the Bell System (January 1, 1984) to describe the long-distance carriers that competed with AT&T Long Lines.As a result of the Modified Final Judgement (MFJ) that caused the reorganization of the Bell System, AT&T and the OCCs became known as interexchange carriers (IXCs, or IECs) and initially were not allowed to provide intraLATA long distance service. See also Bell System, IXC, LATA, long distance, and MFJ.

Webster's New World Telecom