High biologic drug prices have placed substantial strain on the US health care system. The Biologics Price Competition and Innovation Act (BPCIA), passed in 2010 as part of the Affordable Care Act, created an abbreviated approval pathway for biosimilars-versions of "originator" biologic drugs made by different manufacturers-to help address this issue. However, a decade after its passage, the BPCIA has spurred only limited competition. We examined the role that litigation has played in this muted success, reviewing all lawsuits related to the BPCIA filed between its enactment and August 1, 2020. Our review identified two key problems: noncompliance with steps in the complex litigation process established by the BPCIA and large numbers of patents enforced by originator manufacturers. Both actions have contributed to frequent confidential settlements between originator and biosimilar manufacturers that have delayed the availability of biosimilars. To facilitate more timely biosimilar entry, policy makers should consider limits on patent prosecution, compulsory public patent listing, and enhanced antitrust enforcement.