It is retaliation for another business competing with you. That is literally using your market power to try to reduce competition.

But taking anti-competitive actions by itself isn't necessarily an issue, but it is a problem if you're deemed to have significant market power in a defined market.

Essentially: if Facebook is deemed to have significant market power, this could be a problem, if it doesn't have, then it isn't a problem.

Anti-trust relies heavily on the precise definition of a market (which is a subject that Hacker News comments generally ignore when crying wolf, I mean, monopoly).

I don't think its anti-competitive considering they don't need to provide any third party APIs at all. Plus it's not like to create a social app you absolutely need FB login or FB data. I think if your company can't make it and you're blaming FB for not giving you enough data maybe your business model was a little too dependent on Facebook in the first place.

> I don't think its anti-competitive considering they don't need to provide any third party APIs at all.

Removing the access of a competitor in retaliation for them competing with you, when you give it to other players is anti-competitive by definition.