Nilepet is examined as a state-owned enterprise that simultaneously manages extraction and reproduces elite patronage within a rentier political settlement in South Sudan, with comparative reference to Sonangol, NNPC, and GEPetrol. The study asks how a patronage-based SOE equilibrium structures political order across the independence period and the post-2013 conflict economy, drawing on SOE governance theory, developmental state debates, and rentier-state approaches to national oil companies. Using corporate governance analysis of company architecture and reporting, comparative assessment of SOE governance trajectories, and interviews alongside institutional evidence from the petroleum sector, the analysis shows that the phenomenon is not best understood as a discrete policy failure or short-lived crisis. Rather, it is sustained through interconnected institutional and political mechanisms that reshape incentives, authority, and resource access over time. Across the cases, the study traces how these mechanisms operate in practice, the variation they generate, and why reform agendas that overlook underlying political settlements rarely succeed. It offers both a conceptual synthesis and a grounded comparative interpretation of Nilepet within a broader political economy of state-owned enterprises. The study concludes that durable reform requires institutional redesign, political bargaining, and accountability strategies capable of reaching the effective sites of power within resource governance systems.