Microsoft has sued TiVo over the unauthorized use of technology related to the purchase and delivery of video.
The suit - filed in a San Francisco federal court - also alleged that TiVo illegally deployed patented technology to display programming information on its set top boxes.
According to Roger Cheng of the WSJ, the legal offensive was initiated simply to counter an earlier case filed by TiVo against AT&T - as t he latter corporation reportedly uses Microsoft's technology in its various television services.
"Microsoft is standing up for AT&T because the telecommunications company is the largest and most influential customer of its Internet video platform," explained Chen.
"When AT&T chose to go with an Internet-based TV service, it opted to work with Microsoft, which powers the video delivery platform, as well as the digital video recording technology. As a result, it feels the need to shoulder the legal burden for AT&T."
Unsurprisingly, TiVo has thus far rejected Microsoft's offer to resolve the impasse by signing a licensing agreement.
"Microsoft's recent legal actions, including its decision to seek to intervene on behalf of its customer, AT&T, and its recent complaint against TiVo in US District Court, Northern District of California do not bear on whether the AT&T products and services that are the subject of TiVo's complaint infringe the patents asserted by TiVo," the company claimed in an official statement.
"Rather these actions are part of a legal strategy to defend AT&T. We remain confident in our position that AT&T will be found to infringe on the TiVo patents asserted."
Meanwhile, UberGizmo noted that a legal victory by Microsoft would "effectively" block TiVo from selling DVRs without a licensing deal.
"This suit is similar to AT&T's lawsuit against TiVo, claiming that the media boxes violate patents from AT&T's VDSL-based U-Verse service."