Online platforms, such as Google, Facebook, or Amazon, are constantly expanding their activities, while increasing the overlap in their service offering. In this paper, we study the scope and overlap of online platforms' activities, when they are endogenously determined. We model an expansion...

In this paper, we analyze the impact of cooperation on R&D investments in a two-sided market, where platforms compete in quantities. We show that if indirect externalities are of a moderate magnitude, the threshold degree of spillovers above which cooperation spurs R&D investments and enhances...

Strategic interactions between two-sided platforms depend not only on whether their decision variables are strategic complements or substitutes as for one-sided firms, but also - and crucially so - on whether or not the platforms subsidize one side of the market in equilibrium. For example, with...