The World Health Organization (WHO) Pathogen Access and Benefit-Sharing (PABS) system, established under Article 12 of the WHO Pandemic Agreement, aims to promote timely sharing of pathogen materials and sequence information with pandemic potential while ensuring fair and equitable benefit-sharing. Proposed in response to inequities exposed during the coronavirus disease 2019 (COVID-19) pandemic and limitations in existing arrangements, the PABS annex remains under negotiation within the Intergovernmental Working Group. This article analyses the institutional background, core design, and key areas of contention in the PABS system. It highlights three challenges: Defining key terms and scope, designing benefit-sharing and allocation mechanisms, and establishing operational and governance arrangements. It also proposes recommendations to strengthen clarity, feasibility, and institutional coherence for pandemic preparedness and response. © 2026