Suárez would have to sue them for breach of contract I suppose. I don't think he's bothered right now.
Honestly, I'm pretty sure Suárez or his agent would have pressed the clause if Suárez really wanted to go to Arsenal.
Wasn't there some ambiguity in the clause that Liverpool exploited? Something like it said that Liverpool had to allow Suarez to talk to any club that bid £40m, but it didn't spell out that they had to sell him.
that's what a release clause IS. You can't actually force a player to leave, he can just refuse to enter into contract negotiations. But if his release clause is met, then if he wants to go he can go for that price. Liverpool did tell arsenal to f*** off, which technically they weren't allowed to do, but Suarez will just say he told liverpool he wasn't interested if arsenal ever tried to do anything about it.
Interestingly enough, when Messi was 17 he had a release clause of 140+ mil, and it was met by AC milan but he decided against the move. Whoever that talent scout was, get him to the toon please.
Normally you'd be correct but the reply earlier was in fact correct. The £40m was allowed to talk only not the purchase price bizarrely. Basically Liverpool tricked Suarez and his agent which they only discovered later in the small print as such.