the clayton antitrust act of 1914 and the robinson-patman act of 1936 outlawed what
Robinson–Patman Act The law grew out of practices in which chain stores were allowed to purchase goods at lower prices than other retailers. An amendment to the Clayton Antitrust Act, it prevented unfair price discrimination for the first time, by requiring that the seller offer the same price terms to customers at a given level of trade. The Act provided for criminal penalties, but contained a specific exemption for "cooperative associations".