That bit is about Chrome OS (ie, a chromebook), not Chrome itself. The bit about it being "non-unique" means it's not a GUID - other people's devices will send

That bit is about Chrome OS (ie, a chromebook), not Chrome itself. The bit about it being "non-unique" means it's not a GUID - other people's devices will send the same tag. It does not identify you. > To clarify, my point was that Google has a GUID (your Google account, and likely other forms of ID) that identify you pretty clearly across devices/Chrome instances. I think the privacy policy is quite clear that Chrome does nothing here that other browsers don't do. Obviously if you have a Google cookie from signing in to the website then that's going to identify you pretty clearly, but that's just how cookies work, and would be exactly the same in any other browser. I'd like to specifically direct your attention to the first three paragraphs of the policy, and in particular: "If you use Chrome to access other Google services, such as using the search engine on the Google homepage or checking Gmail, the fact that you are using Chrome does not mean that Google will receive any special or additional personally identifiable information about you." > I saw nothing in the policy you linked that said Google AdSense and other Google ad services (DoubleClick tags, GA, etc.) do not use that information to link identities across devices for purposes of tracking. I wouldn't expect to find any information about how AdSense works in the Chrome policy. The privacy policy for ads is over here and discusses this topic: http://www.google.co.uk/policies/technologies/ads/ http://www.google.co.uk/policies/technologies/ads/