Coordinated Pricing Rules in Network Oligopolies

Network oligopolies with sequential or multi-part consumption face double marginalisation across complementary components, motivating constraints on inter-firm pricing. Building on regulatory provisions permitting coordinated pricing for composite or multi-firm products, we study pricing rules that benchmark cross-firm prices against firms’ standalone or bundled prices. Coordination is not inherently welfare improving: discount-based benchmarks can generate equilibrium surcharges. By contrast, a no-discount rule, NDB, ties cross-firm pricing to own-firm bundles, internalising complementarities without propagating markups and raising welfare across a wide range of market sizes and demand parameterisations. However, private and social incentives need not align, so welfare-improving coordination need not arise endogenously. Whilst these results apply broadly to coordinated pricing in network industries, a calibration to the UK bus market illustrates quantitative relevance. NDB delivers substantial consumer-surplus gains (around 20%) and increases ridership, generating external benefits comparable in magnitude to current operating subsidies, up to £0.5 billion p.a.