This paper explores the incentives for, and the effects of, collusion in prices between two-sided platforms. We … a single side of the market. Under two-sided collusion, prices on both sides are higher than competitive prices …-group externalities makes two-sided collusion at a given profit level harder to sustain, and reduces the harm from collusion suffered by …

and compare two forms of collusion: in the first, publishers cooperatively select both prices and political position; in … differentiation outcome does not depend on the size of the advertising market. We thus show that collusion on prices reinforces the …

As auctions are becoming the main mechanism for selling advertisement space on the web, marketing agencies specialized … in bidding in online auctions are proliferating. We analyze theoretically how bidding delegation to a common marketing …

We present an empirical investigation of the role of marketing agencies in Google's online ad auctions. By combining … data on advertisers' affiliation to marketing agencies with data on bidding in ad auctions, we analyze how changes in the …

other business buyers. Using a proprietary dataset of secondary market auctions hosted on an online B2B platform, we study … how market pricing information from other auctions for comparable products a ffects the bidding behavior of the first … behavior and concurrent prices, formed from other open and just-finished auctions relative to the focal auction. We also study …