When do carbon markets reduce inequality? Article 6 transfers under alternative futures

We assess whether Article 6 carbon market transfers reduce between-region income inequality. Using an integrated assessment model (GCAM) with endogenous regional GDP, we model a maximalist form of Article 6 cooperation, with internationally transferred mitigation outcomes (ITMOs) traded across 32 regions under three socioeconomic baselines (SSP1, SSP2, SSP4) and a net-zero 2050 pathway. Our primary metric is the population-weighted global Gini coefficient, which we decompose into policy burden and transfer components and examine across the regional income distribution. Article 6 reduces inequality under most scenarios, with Gini reductions of 0.5 to 0.9 points by 2050 under SSP1, SSP2, and net-zero pathways. Under SSP4, where income divergence erodes lowerincome regions' comparative advantage in low-cost mitigation, the progressive effect weakens to nearneutral (+0.03 Gini points). The financial transfer effect dominates the policy burden effect by a factor of three to six. Theil decomposition confirms this operates overwhelmingly through the betweenregion channel under convergent scenarios, weakening to 79 percent under SSP4. Africa's position as net seller or buyer serves as a diagnostic of this dependence. Article 6 can reduce global inequality, but the outcome depends on underlying development conditions rather than the market mechanism itself.