During the past year, Match Group (MTCH) stock has been red-hot, going from $19 to $48. And the main driver: the huge growth in Tinder. But not everyone is happy. Three of Tinder’s founders and some current executives filed a massive lawsuit. The allegation is that they have been cheated out of $2 billion in stock option compensation. Now judging the outcome of the case is far from easy. Yet it does show the perils of negotiation for equity.