Yes, yes it does. You'll need to refine your brief assertion to make it correct. It's all anonymized of course, but Facebook absolutely has many commercial agreements to share its user data with partner companies. A common part of these agreements, for example, is for the partner companies to also share their user data with Facebook.
I've worked at Facebook for four years. No, no we don't, no matter what the "guy you know" says. Harrison already provided you with our very strongly worded, official claims to that effect.
Since you're the one claiming otherwise, how about an actual, verifiable example? "Company X paid Facebook $Y for user data Z" doesn't sound like an unreasonably specific request.
I see. Money must not be explicitly trading hands in these commercial data-sharing agreements, because you're very serious about that one detail (and nothing else). I obviously don't have insight into these commercial data-sharing contracts - actually, you do. So I'll assume I'm wrong about dollars being exchanged directly.
But I'm not wrong that data is shared liberally and unnecessarily in these data-sharing agreements, which was actually the point. And I'm not wrong that those agreements are commercial in nature with Facebook receiving something in return. Or are you saying Facebook's data-sharing agreement system is a giant charity program. So I'm still okay with calling commercial data-sharing agreements "selling user data."