A division of the World Wide Web Consortium (W3C) has rejected Google’s alternative to 3rd party cookies, “Topic API”.
While Google says that Topics API will protect Web users from “unwanted tracking & profiling,” Amy Guy of the W3C’s Technical Architecture Group (TAG) indicated in a Github post that TAG’s initial assessment is that it would not be able to achieve the claimed objectives.
Here’s what Amy writes:
The intention of the Topics API is to enable high level interests of web users to be shared with third parties in a privacy-preserving way in order to enable targeted advertising, while also protecting users from unwanted tracking and profiling. The TAG’s initial view is that this API does not achieve these goals as specified.
The Topics API as proposed puts the browser in a position of sharing information about the user, derived from their browsing history, with any site that can call the API. This is done in such a way that the user has no fine-grained control over what is revealed, and in what context, or to which parties. It also seems likely that a user would struggle to understand what is even happening; data is gathered and sent behind the scenes, quite opaquely. This goes against the principle of enhancing the user’s control, and we believe is not appropriate behaviour for any software purporting to be an agent of a web user.
The responses to the proposal from Webkit and Mozilla highlight the tradeoffs between serving a diverse global population, and adequately protecting the identities of individuals in a given population. Shortcomings on neither side of these tradeoffs are acceptable for web platform technologies.
It’s also clear from the positions shared by Mozilla and Webkit that there is a lack of multi-stakeholder support. We remain concerned about fragmentation of the user experience if the Topics API is implemented in a limited number of browsers, and sites that wish to use it prevent access to users of browsers without it (a different scenario from the user having disabled it in settings).
We are particularly concerned by the opportunities for sites to use additional data gathered over time by the Topics API in conjunction with other data gathered about a site visitor, either via other APIs, via out of band means, and/or via existing tracking technologies in place at the same time, such as fingerprinting.
