Robert H. Jackson, Bruce's Juices v. American Can Company…
“ No one contends that the Act makes illegal all contracts of sale at a discount. Nor does any one deny that an illegal discrimination becomes apparent only after there have been two or more sales. As the Court states, a contract may be made today which has no legal defect under the Robinson-Patman Act. But once there are two or more sales and once there has been illegal discrimination, the illegality may reach back to the first transaction, which was free of all defects when made. That is inherent in the very nature of discrimination and it should not surprise us to discover that fact. ”
