One of the primary federal antitrust laws. The Clayton Act specifically prohibits price discrimination (selling to different buyers at different, discriminatory prices) (Section 2(a), as amended by the Robinson-Patman Act), tying arrangements, exclusive dealing, and corporate expansion if these activities substantially lessen competition or create a monopoly. It also prohibits interlocking corporate directorships where the corporations are competitors; no individual may simultaneously serve on the boards of directors of two or more competing corporations, if one of the corporations has assets over one million dollars.