FB and LinkedIn ask for contacts (or at least used to). That's dozens of people's data, with at least one unique identifier for each, who did not provide inform

FB and LinkedIn ask for contacts (or at least used to). That's dozens of people's data, with at least one unique identifier for each, who did not provide informed consent in any way. So you are as safe as the most apathetic or technically ignorant of your acquaintances, and FB's shadow profile grows again.