Pente, much like Gomoku, is known to favor the first player heavily. The Pro Tournament Rule, proposed by Tom Braunlich, was adopted for standard tournament play as an attempt to mitigate this advantage and bring the win ratio at high level play closer to around 50% as is roughly the case in casual play. Analyzing the data of around 750,000 games played online at Pente.org bears this out and shows a bias of about 53% across all games and skill levels.