SiriusXM sued for patent infringement.

It seems that Digital Stream IP, LLC is at it again, filing another patent infringement suit in U.S. District Court in Delaware, this time against the satellite radio giant. The lawsuit follows those filed against iHeartMedia, CBS Radio, and several car manufacturers, in which Digital Stream alleges infringement upon its patent for a “Wireless Music and Data Transceiver System.” Digital Stream alleges that by using a “digital music transmitter,” combining a number of streams onto a single frequency and then demodulating the streams back into individual channels, SiriusXM is infringing. Meanwhile, a group that goes after “patent trolls” by challenging the underlying patents issued by the U.S. Patent Office, Unified Patents, Inc., has challenged the Digital Stream patents as obvious, unpatentable, and/or conflicting with prior art and patents; the Patent Trial and Appeal Board has instituted an inter partes review of the key patent in question. (For those among us who are not attorneys, “inter partes”—Latin for “between the parties.”—refers to a trial proceeding involving the Patent and Trademark Office to challenge the validity of a patent.)