Playing Fair in the Privacy Sandbox: Competition, Privacy and Interoperability Standards

Google’s Privacy Sandbox proposals to change the Chrome browser in ways that are likely to further advantage them over other publishers and advertising platforms has attracted the attention of competition regulators, the online advertising industry, and critics of their platform power. At the same time, the Privacy Sandbox appears to answer a call from data protection regulators, privacy advocates and users for ‘privacy by design,’ moving in lockstep with its industry peers. How, then, should this behaviour be evaluated for abuse? I argue that there are several hurdles to considering the most controversial Privacy Sandbox proposal – blocking third-party cookies – as an abuse of market power. Furthermore, I propose that, because web browsers are an architecturally regulated market, competition regulators should distinguish unilateral behaviour by examining it in the context of other browsers’ behaviours, along with signals regarding consensus from the relevant standards bodies.