Here's why:
* Patents protect inventions, not games. Patents typically cover new and useful inventions, not the concept of a board game or its rules.
* Game mechanics are usually protected by copyright. The specific design of the board, the rules, and the questions in Trivial Pursuit are likely protected by copyright, which prevents unauthorized copying.
* The name "Trivial Pursuit" is likely a trademark. The name itself is likely protected by a trademark, which prevents others from using it commercially.
So, while the Trivial Pursuit board game itself isn't likely patented, its specific elements are probably protected by copyright and trademark.