LEGALITY : Cash-based tournaments in games of skill are not considered gambling because the generally accepted definition of gambling involves three specific things:
(1) the award of a prize,
(2) paid-in consideration (meaning entrants pay to compete) and
(3) an outcome determined on the basis of chance. Without all three of these elements, a competition that reward real prizes is not gambling. In the case of Pro Gamers League tournaments, outcomes are not determined by chance, but are rather achieved through a player’s skill or ability, making these tournaments perfectly legal.