Microsoft received the rights to an updated patent that describes the addition of an external hard drive to the Xbox 360 game console.
The original patent application was filed in December 2004, or almost one year before the introduction of the Xbox 360, and granted in September 2010. The update was filed in April 2011.
The content of the patent is almost entirely unchanged, but Microsoft added 15 more references of prior art, one of them dating back to 1967, which describes a "Circuit breaker box and operator with improved lever and interlock means", and one other patent referring to an "encryption device interlock" invention from 1978 that explains a connector interlock plate for an electronic device cabinet.
Microsoft's patent details the addition of an external HDD to the Xbox 360, specifying the way how the device is attached and supported by the console frame.