Halo 4 leak, and working with law enforcement to address the issue.
Images have surfaced on social sites NeoGAF and Reddit, depicting two Halo 4 retail discs, and the Xbox 360 dashboard featuring the game ready to be played.
"We have seen the reports of 'Halo 4' content being propped on the Web and are working closely with our security teams and law enforcement to address the situation," a Microsoft spokesperson told Joystiq.
In clarifying whether the images represent the actual artwork featured on retail copies of Halo 4, Microsoft explained the need for two discs.
According to the publisher, Halo 4's second disc "contains data that will need to be installed on an Xbox 360 hard drive or compatible flash storage device with at least 8GB of available memory in order to access 'Halo 4's' extensive suite of multiplayer features." Microsoft has employed a similar system for first-party games like Forza Motorsport 4.
Once the data is installed only the first disc will be required to access Halo 4's single- and multiplayer content.