Auctions in Private Internet Advertising

Several recent research projects have designed systems that address the problem of user privacy in online advertising systems. The primary goal of these systems is to allow for targeted advertising without revealing user profiles to the ad network. None of these designs, however, adequately consider the role of the auction. This paper looks at the problem of running auctions that leverage user profiles for ad ranking while keeping the user profile private. We define the problem, broadly explore the solution space, and describe the pros and cons of these solutions in light of the proposed private advertising systems. We analyze the performance of our solutions using data from Microsoft Bing advertising auctions. We conclude that, while none of our auctions are ideal in all respects, they appear to be quite feasible in practice.