For several years, an increasing number of ¯rms are investing in Open Source Software (OSS). While improvements in such a non- excludable public good cannot be appropriated, companies can bene¯t indirectly in a complementary proprietary segment. We study this incentive for investment in OSS....

The existing literature on "two-sided markets" addresses partici- pation externalities, but so far it has neglected pecuniary externalities between competing platforms. In this paper we build a model that incorporates both externalities. In our setup di®erentiated platforms compete in...