The Role of Housing Platforms in Facilitating Trading between Firms

We study the 2013 merger of three multiple listings services (MLSes) in Florida, the primary platforms where properties are transacted. We use MLS listings data from 2009 to 2019 to trace out the effects of the merger on the likelihood that listings by brokerages from different platforms are traded. The merger sharply increased the platform scale for brokerages whose platforms were not dominant in a local market prior to the merger. This exposed their listings to more agents and also expanded their access to more listings. Difference-in-difference estimates indicate that nondominant brokerages are more likely to have interplatform trades.