IP Law Daily, PATENT—D. Del.: Summary judgment of non-infringement granted in water meter dispute, (Nov 6, 2025)

By Kevin M. Finson, J.D.

A federal judge ended a patent battle after finding expert evidence lacking.

No genuine question of material fact existed as to infringement of claims related to a water meter and leak detection system because the patentee lacked expert testimony which would be required to show that the accused products practiced the asserted claims, the U.S. District Court in Wilmington, Delaware has held. The patent concerned complex technology and the patentee’s sole expert had been excluded as a discovery sanction, and summary judgment was granted (Rein Tech, Inc. v. Mueller Systems, LLC, No. 1:18-cv-01683-MN, (D. Del. Nov. 5, 2025)).

Rein Tech, Inc. (Rein) was the owner of U.S. Patent No. 11,549,837 (the ’837 patent), which was entitled “Water Meter and Leak Detection System,” and which listed Michael Klicpera, the founder and president of Rein, as the sole inventor. Rein brought suit for infringement of the ’837 patent, among others which were eventually removed from the case, against Mueller Systems, LLC. After claim construction and the completion of discovery, the court excluded the testimony of Mr. Klicpera, Rein’s sole designated expert, due to repeated and flagrant violations of a protective order under which certain material had been designated “RESTRICTED – ATTORNEY’S EYES ONLY.” Rein did not seek leave to designate a replacement expert after that sanction was imposed, but two months later disclosed during a teleconference that it intended to call two new experts who had not yet met with Rein’s counsel and who had not yet begun drafting reports. The court determined that it would not allow replacement experts at such a late stage in the litigation. Mueller moved for summary judgment of non-infringement and invalidity of the asserted claims.

Infringement. Mueller argued that Rein had not offered any evidence that its accused products contained the “setting limitation” found in claim 42 of the ’837 patent. Absent any admissible expert testimony, Rein argued that its claim charts, along with two brochures and a YouTube video, adequately established the presence of that limitation. The court found each of these allegations barebones and conclusory, noting that none of them explained how the accused products included the limitation in question. The court held that Rein would be unable, as a matter of law, to meet its burden at trial.

The court granted the motion for summary judgment of non-infringement and declined to reach Mueller’s arguments on invalidity.

The case is No. 1:18-cv-01683-MN.

Judge: Noreika, M.

Attorneys: J Jackson Shrum (Jack Shrum, P.A.) for Rein Tech, Inc. Cortlan S. Hitch (Morris James LLP) for Mueller Systems, LLC.

Companies: Rein Tech, Inc.; Mueller Systems, LLC

Cases: Patent DelawareNews