AT&T; doesn’t have to share certain technology.

U.S. District Judge Harold H. Greene, who ordered the breakup of American Telephone & Telegraph, ruled that AT&T; does not have to share its sophisticated 800 data base with competitors. Greene turned down a request from the Justice Department asking that portions of AT&T;’s Common Channel Interoffice Signaling data be made available to other phone companies, new and old, until they can develop their own systems.