Prime Faces Federal Antitrust Suit Over Pharmacy Reimbursement Practices

According to Bloomberg Law, which first reported the lawsuit, the complaint was filed July 2 in the U.S. District Court for the Western District of Washington by Trust LLC, an entity representing the claims of approximately 5,000 pharmacies. Bloomberg Law reported that the group turned to federal litigation after alleging its efforts to pursue Prime’s contractually required arbitration process were unsuccessful.

The lawsuit centers on pharmacy network agreements used by pharmacy benefit managers (PBMs), which negotiate prescription drug benefits and reimbursement terms on behalf of health insurers, employers and government health plans. Trust alleges Prime improperly aligned reimbursement rates with those established by Express Scripts, one of the nation’s largest PBMs, rather than independently determining payment terms. According to Bloomberg Law, the plaintiffs contend that arrangement unlawfully depressed reimbursement levels paid to participating pharmacies.

The allegations highlight continuing concerns over competition in the PBM industry, where a small number of companies administer prescription drug benefits for a substantial share of the U.S. market. PBMs negotiate with drug manufacturers, pharmacies and health plans, placing them at the center of debates over prescription drug pricing and pharmacy access.

The claims against Prime and Express Scripts resemble allegations raised in earlier litigation. In 2024, independent pharmacies filed a proposed class action alleging that Prime and Express Scripts entered into an agreement under which Prime adopted Express Scripts’ reimbursement schedules while continuing to operate independently, conduct the plaintiffs argued amounted to unlawful price-fixing under federal antitrust law.

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The companies have also faced scrutiny from state regulators. In April 2025, Michigan Attorney General Dana Nessel sued Prime Therapeutics and Express Scripts, alleging the companies conspired to suppress payments to independent pharmacies and reduce competition. The state alleged the arrangement harmed pharmacies, limited patient access to prescription services and contributed to market concentration in the PBM sector. Both companies have denied wrongdoing in that litigation.

The latest lawsuit arrives as federal and state policymakers continue examining the competitive effects of the PBM industry. Regulators have increasingly focused on whether dominant PBMs use their market position to influence reimbursement rates, pharmacy network participation and drug pricing practices. Recent enforcement actions and legislative proposals have sought greater transparency and oversight of PBM business practices.

Prime Therapeutics, which is owned by a consortium of Blue Cross and Blue Shield health plans, is significantly smaller than Express Scripts but serves millions of covered lives through employer and health-plan clients. Express Scripts operates as part of Cigna’s health services business and ranks among the largest PBMs in the United States.

The Washington lawsuit remains in its early stages. According to Bloomberg Law, the complaint seeks relief on behalf of approximately 5,000 pharmacies and follows the plaintiffs’ unsuccessful attempts to pursue the dispute through arbitration. Court proceedings are expected to determine whether the antitrust claims will move forward as the litigation progresses.

Source: Bloomberg Law