Kenyon obtained a summary judgment of non-infringement for Volkswagen AG, Audi AG, and Volkswagen Group of America, Inc. in the US District Court for the Eastern District of Texas. Plaintiff MHL Tek, LLC had accused nine automakers of infringing US Patent Nos. 5,663,496, 5,731,516, and 5,741,966, which relate to tire-pressure monitoring systems. In March 2009, the court granted motions to dismiss MHL’s claims for infringement of the ’496 and ’966 patents for lack of standing. The only patent that remained in suit was the ’516 patent, entitled "System and Method for Monitoring a Pneumatic Tire." According to the claims, the tire-pressure sensor must be contained within a housing that is “cylindraceous,” which the court construed to mean "generally cylindrical." Volkswagen and Audi argued that their tire-pressure sensors were not “generally cylindrical," and also argued that narrowing amendments made during prosecution prevented MHL from asserting infringement under the doctrine of equivalents. The district court agreed. Case number 2:07-cv-289-TJW (2010).