Why rely on someone else's go-ahead if you can just do something different? They didn't patent it for no reason - they want a cut if someone using it makes a bunch of money, and likely won't give you the go-ahead without that guarantee.

Sega applied for and was awarded U.S. Patent 6,200,138 – "Game display method, moving direction indicating method, game apparatus and drive simulating apparatus" – in 2001. The mechanics in the "138 patent" describe an arcade cabinet similar to Sega's previous arcade game Harley-Davidson & L.A. Riders (1997), but also describe the arrow navigation system and pedestrian avoidance aspects that were used in Crazy Taxi.

In 2001, Electronic Arts and Fox Interactive released The Simpsons: Road Rage, which reviews identified as being clearly inspired by the gameplay of Crazy Taxi. In this game, the player controlled one of The Simpsons characters as they drive around Springfield, bringing passengers to these destinations in a way like in Crazy Taxi. In December 2001, Sega brought Fox Entertainment, Electronic Arts, and developer Radical Games Ltd. to court over this infringement of the 138 patent. The case, Sega of America, Inc. v. Fox Interactive, et al., was settled in private for an unknown amount. The 138 patent is considered to be one of the most important patents in video game development.