Context: Currently, two major pool administrators manage programs licensing standard-essential patents (SEPs) for High-Efficiency Video Coding (HEVC), a central standard for high-resolution video (such as 4K): Access Advance and Via Licensing Alliance. In December, it was revealed by Düsseldorf-based patent firm Cohausz & Florack that, together with litigation firm Krieger Mes, Via LA licensors had filed “patent infringement suits against Microsoft based on HEVC SEPs [standard-essential patents]” toward the end of November December 20, 2024 ip fray article). Microsoft is both a licensee and a licensor in Access Advance’s HEVC pool.
What’s new: Three of Via LA’s HEVC pool licensors, M&K, Gensquare LLC, and Tagivan II have sued Microsoft in the Landgericht Dusseldorf (Düsseldorf Regional Court), enforcing seven standard-essential patents and seeking an injunction. They allege that Microsoft uses their HEVC patents in some of its most popular products, including Windows 10, Windows 11, its Surface tablets, and its Xbox consoles. The company is also selling an HEVC extension as an add-on to its operating system at a price point that the licensors allege would cover royalties to both existing patent pools that cover HEVC patents (Access Advance being the other one). The suits were filed individually between November 26, 2024 and March 6, 2025. All three were served as of last week.
Direct impact and wider ramifications: The licensors are, of course, seeking the “silver bullet” that is an injunction against Microsoft, counsel for the licensors Gottfried Schüll of Cohausz & Florack, told ip fray. The infringing HEVC technologies are not only present in Microsoft’s Windows 10, Windows 11, Surface tablets, and Xbox consoles, but the company also sells HEVC decoders on its website shop – for which it does not pay royalties, counsel said. “So we believe there will be an effect if an injunction is granted,” Mr. Schüll added.
The patents being enforced, according to a spokeswoman for the Dusseldorf Regional Court, include:
M&K:
- EP2608541 (“Method for decoding intra-predictions”) (case number: 4a O 6/25)
- EP3051815 (“Apparatus for decoding an image”) (case number: 4a O 12/25)
Gensquare:
- EP3829172 (“Method of constructing merge list”) (case number: 4c O 6/25)
- EP2942954 (“Image decoding apparatus”) (case number: 4c O 9/25)
Tagivan II:
- EP2779644 (“Image decoding method and image decoding device”) (case number: 4b O 69/24)
- EP2775717 (“Video decoding method and video decoder”) (case number: 4b O 4/25)
- EP3598754 (“Signaling of luminance-chrominance coded block flags (cbf) in video coding”) (case number: 4b O 5/25)
The spokeswoman also informed ip fray that Tagivan II LLC was the first to enforce its patents, on November 26, 2024, while Gensquare filed its suit on February 24, 2025, and M&K sued Microsoft on March 6, 2025.
Because the two programs have overlapping licensors, Microsoft’s license to the Access Advance HEVC pool means it also licenses a certain share of the patents in Via LA’s HEVC program. M&K, Gensquare LLC, and Tagivan II collectively own 90% of the remaining unlicensed patents.
In a statement today, Via LA President Heath Hoglund said the company’s HEVC patent pool has been available for 10 years and offers an “efficient way” to license a large, essential portfolio of IP. He added:
“Our licensors have patiently engaged the market. Unfortunately, many implementers of the technology remain unlicensed, so the time has come for the patent holders to enforce their rights.”
Mr Hoglund believes Via LA’s HEVC patent pool is the most efficient way to license essential IP and hopes more implementers will join the 500 licensees already part of that pool.
Cohausz & Florack’s Mr. Schüll told ip fray that while the team had eyed the Unified Patent Court as a venue, they eventually decided to file in the Düsseldorf Regional Court, given its extensive case law in patent pool litigation – and its efficiency. The judges are very qualified, the parties involved “very much respect” the outcome of these proceedings, and the ability to request an injunction is a good basis to restart negotiations, he added.
When asked whether this could lead to a wider, global enforcement campaign, Mr. Schüll said this has been uncommon in such disputes, especially those involving Via LA licensors. “Germany has been proven a very effective venue for these types of cases, and while there have been a couple of instances where there were parallel cases in the U.S. and UK, it’s rare,” he noted.
Counsel
Representing the plaintiffs alongside Mr. Schüll is Axel Verhauwen of Krieger Mes, as well as a team at Cohausz & Florack: Dr. Christoph Walke (who is also frequently counsel for Nokia), Dr. Fabian Vogelbruch, and Dr. Henning Sternemann. This team has represented Via LA (previously MPEG LA) licensors in several suits before and has achieved favorable settlements in numerous H.264 cases. It has been asserting H.265 SEPs since 2022.
On Microsoft’s side is a Bardehle Pagenberg team led by Professor Tilman Mueller-Stoy and Dr. Christian Haupt.