Plaintiff SSI Technologies, LLC alleges that its competitor, defendant Dongguan Zhengyang Electronic Mechanical LTD (DZEM), infringes two SSI patents on automotive fluid sensors. DZEM denies infringement, contends that the patents are invalid, and accuses SSI of tortious interference with its business relationships. Both sides have moved for summary judgment on various issues. Dkt. 92 and Dkt. 98. Infringement turns on issues of claim construction, and the court concludes that DZEM does not infringe either patent. DZEM does not suggest that it faces any further threat of enforcement under the patents-in-suit, so the court need not consider the validity of the patents. The court will grant SSI’s motion for summary judgment on DZEM’s tortious interference counterclaim. The several pending motions involving evidentiary and discovery disputes are denied as moot. BACKGROUND The patents-in-suit involve fluid sensors, specifically sensors that check the purity of diesel exhaust fluid used in emission-reduction systems. Diesel exhaust fluid is a mixture of water and urea, injected as a mist into diesel exhaust. The diesel exhaust fluid reacts with Case: 21-2345 Document: 1-2 Page: 31 Filed: 09/23/2021 (35 of 58) 2 nitrous oxide in the exhaust, breaking it down into nitrogen, water, and carbon dioxide, thereby reducing the more harmful emission of nitrous oxide. If the diesel exhaust fluid is contaminated, the effectiveness of the nitrous oxide reduction system is reduced and contamination may damage the system. SSI and DZEM are competitors in the automotive-sensor market; they both make and sell sensors that detect contamination in diesel exhaust fluid. SSI contends that DZEM’s sensor infringes the two patents-in-suit. The first patent-in suit, U.S. Patent No. 8,733,153, discloses and claims a sensor system that measures the speed at which sound waves travel through a fluid to determine a quality of the fluid, such as whether a contaminant is present. The second patent-in-suit, U.S. Patent No. 9,535,038, improves the accuracy of such a sensor system by disclosing and claiming a sensor system with a filter that prevents gas bubbles from entering the sensing area.The clerk of court is directed to enter judgment in accordance with this opinion and close this case.IT IS ORDERED AND ADJUDGED that judgment is entered in favor of defendant Dongguan Zhengyang Electronic Mechanical LTD (“DZEM”) against plaintiff SSI Technologies, LLC (“SSI”) on SSI’s claims that DZEM infringed claims 1, 2, 4, 7 and 8 of U.S. Patent No. 8,733,153 and claims 9-13 and 18 of U.S. Patent No. 9,535,038. IT IS FURTHER ORDERED AND ADJUDGED that judgment is entered in favor of SSI against DZEM dismissing DZEM's sham-litigation, tortious-interference, and invalidity counterclaims. In summary, we reverse the district court’s construc tion of the term “filter” as used in the claims of the ’038 patent and vacate the district court’s grant of summary judgment with respect to the ’038 patent. We affirm the district court’s grant of summary judgment with respect to the ’153 patent and DZEM’s counterclaim for tortious in terference. We vacate the dismissal of the invalidity coun terclaim regarding the ’038 patent but affirm the dismissal of the invalidity counterclaim regarding the ’153 patent. No costs. AFFIRMED-IN-PART, REVERSED-IN-PART, VACATED-IN-PART, AND REMANDED