I think the issue here is that Kaggle's statement that the top teams broke the rules is just very opaque. They stated they broke the rules on external data. The

I think the issue here is that Kaggle's statement that the top teams broke the rules is just very opaque. They stated they broke the rules on external data. The article then goes on to talk about what data the teams used and what licenses it has, and what data the teams were asked to provide. But it really is almost impossible to know what the concerns of FB/Kaggle were without them specifically stating them. Clearly whatever the issue was it didn't effect every team - so it may be there were details of the licenses that the disqualified teams used that weren't good enough. As I say though, it's very difficult to say and it's kind of hard to think of a reason Facebook would arbitrarily disqualify teams for no good reason. It's perfectly possible FB were concerned about image rights or something else, but people seem to be perfectly happy just assuming some grand conspiracy.