This paper challenges the common assumption of market segmentation in international trade. To analyze export entry and pricing decisions of firms in integrated vs. segmented markets, we develop a novel tractable approach based on stochastic export costs that allows us to compare firm-level and...

We study the gains from trade in a model with oligopolistic competition, heterogeneous firms and innovation, and provide a formula to decompose the mechanism. The new insight we provide is that market concentration can be a welfare-relevant feature of market power above and beyond markup...