I have two Facebook accounts: A, and B.
FB account A uses my real email address and has my real life friends.
FB account B uses made up information and is in no way associated with my real life.
I recently installed Instagram on mobile using the same email address as FB account B. I have never selected the "Connect to Facebook" or "Connect Contacts" options.
Imagine my surprise when I look at my Instagram friend suggestions and see many of my REAL LIFE friends, people who are ONLY associated with FB account A.
This means somehow Facebook knows or is assuming that email address B is me even though I have never associated my name or any of my friends' names with it.
The only association I can think of is that I connect to Facebook using both accounts on the same devices, and with the same IP address. Otherwise, there should be no association between the two identities.
I haven't authorized Instagram to dig into my contacts or share data with Facebook, but somehow an Instagram account with my fake identity is being associated with my real life Facebook account.
I know that Facebook owns Instagram, but this feels like some kind of invasion of privacy. I know nothing of legal policy, and would like some advice on how to know if this is legal or not. Thank you for reading this.
(side note: my second identity is not being used for any nefarious purposes)