[Argorak]

No, that would be on the person giving them the data _and_ on Facebooks side to check. Facebook never got permission, because the agent giving them the data is not allowed to give permission.

They also cannot make a reasonable assumption that the agent giving away the data _has_ permission and is lying to them.

[argumentum]

There is no concept of "permission" here as freedom of speech is more important. If you don't want people to have your info, don't give it to people. You are perfectly entitled to "unfriend" someone (in real life) if they give away your data without your permission.

Yahoo, hotmail etc, they all used to scoop up contacts when users (willingly, just like they do with facebook) agreed to give them access in exchange for services rendered.

This is totally different from the government (a third party to either transaction) forcing Facebook to give them data (or stealing face book's data).