A bill to amend Section 10 of the Clayton Act to insure effective application of antitrust principles to prevent anticompetitive action by monopoly common carriers.

Amends the Clayton Act to prohibit any domestic telegraph carrier which possesses a 60 percent or greater market share of annual revenues in any tariffed service in interstate commerce from offering any service or facilities in foreign commerce if the effect of such offer would be to lessen competition substantially or to create a monopoly in the international record telecommunications market.