Porter Company v. National Labor Relations Board
Donald C. Winson, Pittsburgh, Pa., for petitioner.
Norton J. Come, Washington, D.C., for respondent National Labor Relations Board.
George H. Cohen, Washington, D.C., for respondent United Steelworkers of America, AFL-CIO, by special leave of Court.
Lawrence M. Cohen, Chicago. Ill., for Chamber of Commerce of the United States, as amicus curiae.
Mr. Justice BLACK delivered the opinion of the Court.