Protecting Your Privacy While Eroding Your Democracy: Apple's and Mozilla's PPAs (Privacy Preserving Ad Attribution) Considered Harmful

These browser vendors have produced browser-based PPA (Privacy-Preserving [Ad] Attribution) technologies that attempt to establish a world where “advertising online happens in a way that respects all of us, and where commercial and public interests are in balance”.1 Unfortunately, after studying each proposal, I predict they will inadvertently lend themselves to further incentivize the publication and spread of low-quality information (including misinformation), polluting the information landscape and threatening democracies worldwide.