> someone's possession of it doesn't diminish your possession of it However someone's possession of data about you may indeed diminish other rights you hold an

> someone's possession of it doesn't diminish your possession of it However someone's possession of data about you may indeed diminish other rights you hold and/or may be used to gain advantage at your expense. This is why we talk about data getting "into the wrong hands". I may not care for my employer to know about my sexual proclivities. I may not care for insurers to know my search history and draw (possibly incorrect) inferences from it. The argument regarding privacy isn't about the potential that others' knowledge of your info diminishes the utility of the data to you (in most cases there is no _personal_ utility). It's about the power to restrict who can use that information as leverage in the advancement of their interests, often to the detriment of your own. It's about preserving agency.