According to Facebook, “Starting July 2, we’re strengthening the requirements for when an advertiser shares Custom Audiences from a customer file— such as with its advertising agency. In these cases, both parties will need to establish an audience-sharing relationship through Business Manager, and agree to our Custom Audiences Terms.”
Note that this doesn’t apply to all ads and targeted ads that you see on Facebook, but are only applicable to Custom Audience advertising, but we suppose it is a start. In addition to gaining consent, advertisers will also need to disclose and declare where they might have gotten the contact info from.
Users will also be given more control and information, such as being able to click a link that lets them know who was responsible for the targeting information, how your contact info was involved, and if you’re not too pleased about it you can block those ads. Of course the onus lies with advertisers being truthful in their claims, and how Facebook plans to police this is unclear.