On Friday, April 14, 2017, Digital Stream IP, LLC filed two separate complaints in federal court in the Eastern District of Texas against CBS Radio Inc. and iHeartMedia, Inc., alleging infringement of U.S. Patent No. 6,757,913 ("the '913 patent").

The '913 patent is directed to sending digital audio signals from a transmitter to a receiver or tuner, which can display, for example, song titles and artists along with playing the corresponding audio. This, of course, sounds routine in this age of ubiquitous digital radio, but the asserted patent claims a history going back to an original patent application filed July 15, 1996.  Due to patent term extensions granted due to delays in patent office processing, the '913 patent is set to expire on July 5, 2018.

In the complaints, Digital Stream alleges that the '913 patent reflects an "improvement in digital audio" devices and systems and "solve[s] the problems of limited range, signal strength, variety of channels, program information available and overall accessibility and ease of use."

The '913 patent has considerable and ongoing litigation history. In 2016, Digital Stream first targeted the automotive industry in suits against General Motors, Honda, Nissan, BMW, and Mercedes-Benz. Digital Stream also asserted the '913 patent in suits against Best Buy and Robert Bosch.  Many of these cases were dismissed in the preliminary stages based on settlement. However, Unified Patents, a company self-dubbed the "Anti-Troll" and dedicated to challenging patents asserted on a mass scale, filed a petition for inter partes review (IPR) before the Patent Trial and Appeal Board (PTAB) in September 2016, asking that certain claims of the '913 patent be found invalid over various prior art references.

On March 14, 2017, the PTAB agreed with Unified Patents' positions and instituted a review of the '913 patent, finding a reasonable likelihood that one or more of the challenged claims would be found unpatentable (invalid).  A final decision, which will issue no later than March 14, 2018, will decide the fate of the challenged '913 patent claims.  Mercedes-Benz filed its own IPR petition in February of this year challenging a different set of claims, and the PTAB will decide whether to institute this challenge of within the next few months.  In the meantime, Digital Stream appears to have turned its attention onto the radio industry.

The lawsuits allege that CBS Radio and iHeartMedia are infringing at least claim 31 of the '913 patent by broadcasting their hybrid digital/analog HD Radio stations. Interestingly, claim 31 is one of the few claims not challenged in the two pending IPR proceedings – although it appears to of a similar scope as those under PTAB review.  Digital Stream specifically points to several HD Radio stations broadcast in Texas, including CBS Radio's 105.3 The Fan, KRLD 1080AM, and Cowboys Radio 24/7, and iHeartMedia's LoneStar 92.5, KERA HD1 and KERA HD2.  Digital Stream is seeking monetary damages and a finding that the case is exceptional, which would entitle it to attorneys' fees under 35 U.S.C. § 285.

To date, no other radio industry companies have been sued. The pending lawsuits are titled as Digital Stream IP, LLC v. CBS Radio Inc., No. 2:17-cv-313 (E.D. Tex.) and Digital Stream IP, LLC v. iHeartMedia, Inc., No. 2:17-cv-315 (E.D. Tex.).

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