Article 1
1. Mannesmannröhren-Werke AG, Vallourec SA, British Steel Limited, Dalmine SpA, Sumitomo Metal Industries Limited, Nippon Steel Corporation, Kawasaki Steel Corporation and NKK Corporation have infringed the provisions of Article 81(1) of the EC Treaty by participating, in the manner and to the extent set out in the grounds to this decision, in an agreement providing, inter alia, for the observance of their respective domestic markets for seamless standard threaded OCTG pipes and tubes and project line pipe. 2. The infringement lasted from 1990 to 1995 in the case of Mannesmannröhren-Werke AG, Vallourec SA, Dalmine SpA, Sumitomo Metal Industries Limited, Nippon Steel Corporation, Kawasaki Steel Corporation and NKK Corporation. In the case of British Steel Limited, it lasted from 1990 to February 1994.