Not long after Microsoft sued Motorola over its Android based handsets, the former has filed another lawsuit against the latter. This time around, Microsoft has accused Motorola of dishonouring its Reasonable And Non-Discriminatory (RAND), an agreement between the two majors over the implementation and sharing of patented technologies.

The bone of contention is the Xbox 360 employing Motorola's proprietary technologies in the form of its 802.11 Wi-Fi architecture and the H.264/MPEG4 video codecs. Microsoft contends that by agreeing to the RAND, Motorola was liable to contribute patents to a "patent pool" accumulating patents from different entities pertaining to a particular technology. Citing the RAND, Microsoft noted Motorola's agreement to allow sharing the 802.11 and H.264 patents with other companies.

Microsoft claims that Motorola overcharged it for the said patent royalties, which is in violation of the 'reasonable' clause of the RAND agreement. Terming Motorola's demands discriminatory, Microsoft said, "Motorola is demanding royalty payments that are wholly disproportionate to the royalty rate that its patents should command under any reasonable calculus." It further added, "Motorola has discriminatorily chosen Microsoft's Xbox product line and other multi-function, many-featured products and software, such as Windows 7 and Windows Phone 7 and products incorporating Microsoft software, for the purpose of extracting unreasonable royalties from Microsoft."

Microsoft's lawsuit implores the court to determine a reasonable royalty for Motorola's patents. The suit also seeks compensation for Motorola's alleged breach of the RAND.