In the case of Blue Shield of Virginia et al. v. McCready, the Supreme Court ruled in favor of a policyholder who sued her health insurance company for antitrust violations. The plaintiff, Mrs. McCready, claimed that Blue Shield's refusal to reimburse her for psychotherapy services provided by psychologists was part of an illegal conspiracy to restrain trade and monopolize the provision of mental health services in violation with Sherman Act Section 2. She argued that this practice favored psychiatrists over psychologists and caused her financial harm as she had to pay out-of-pocket expenses for psychological treatment which would have been covered if performed by a psychiatrist. The court held that even though McCready wasn't a competitor or customer in the psychotherapeutic market where trade was allegedly restrained, she still suffered injury due to higher costs resulting from anti-competitive behavior; thus making her eligible under Clayton Act Section 4 which allows any person injured by an antitrust violation to sue for damages.

In the dissenting opinion for Blue Shield of Virginia et al. v. McCready, Justice Powell argued that the plaintiff, Mrs. McCready, did not have standing to sue because she was not within the class of persons intended to be protected by antitrust laws and had not suffered any injury in her business or property as required under these laws. He contended that allowing such suits would open up a floodgate of litigation from consumers who are only indirectly affected by anti-competitive practices and could lead to excessive damages awards which might deter legitimate competitive behavior among businesses. Furthermore, he believed it would place an undue burden on courts due to complex issues related with determining causation and calculating damages in such cases.