[rlpb]

> I am only telling fb, if you have this user with this email, show him an ad.

You're also telling Facebook "by the way, I have a relationship with someone with this email address". That's personally identifiable information that you're sending to Facebook. Under the GDPR you can only do that if you have the explicit and freely given opt-in permission to do that from each respective person. "By using this site you agree to..." or "by signing up you agree to..." does not qualify as consent under the GDPR.

If the person does not live in Europe and you are not in Europe then the GDPR doesn't apply, of course.

[mdoms]

GDPR absolutely applies whether the vendor is in Europe or not.

[gnicholas]

I think you mis-read the sentence, which describes neither party as being in Europe.