The U.S. Supreme Court case Group Life & Health Insurance Co., also known as Blue Shield of Texas, et al. v. Royal Drug Co., Inc., doing business as Royal Pharmacy of Castle Hills, et al., 1978 revolved around the issue of whether agreements between an insurance company and pharmacies to provide prescription drugs at a fixed cost for policyholders were exempt from antitrust laws under the McCarran-Ferguson Act's "business of insurance" clause. The court held that these agreements did not fall within this exemption because they were not integral to the insurer-policyholder relationship or spreading and underwriting risk - two key aspects defining 'the business of insurance'. Instead, they were ordinary commercial transactions that could potentially violate antitrust laws if found anti-competitive in nature.

The dissenting opinion in the case of Group Life & Health Insurance Co., also known as Blue Shield of Texas, versus Royal Drug Co., Inc. argued that the majority's interpretation was too narrow and failed to consider the broader context of insurance business practices. The justices contended that agreements between insurers and pharmacies were essential for controlling costs and providing affordable healthcare services, thus falling within the 'business of insurance' exemption under McCarran-Ferguson Act. They believed these arrangements did not constitute price-fixing or anti-competitive behavior but rather were necessary mechanisms for managing risk and ensuring financial stability in health care provision. Furthermore, they expressed concern that this ruling could disrupt existing relationships between insurers, providers, and policyholders by subjecting them to antitrust scrutiny without clear justification.