The restaurant Texas Roadhouse is alleging trademark and trade dress infringement against Amarillo Roadhouse and Texas Corral, restaurants operated in Michigan and Indiana. Although I have discussed trademarks and trademark infringement elsewhere on this blog, I have not done so with trade dress.
Trade dress refers to the visual characteristics of packaging, décor, shapes, designs or site layout. Trade dress can be registered as a trademark if it is source-identifying and otherwise meets the requirements of a trademark, but it is usually protected without registration. Additionally, the trade dress must be nonfunctional in order to be protected. For instance, the décor and design of the Cheesecake Factory may be protectable as trade dress; but to the extent that any of that décor or design is functional (e.g., relating to shelter or architecture), it is not protectable.