Both sides in the seven-year legal battle between Caterpillar and Wirtgen over patent infringement on their road milling machines have won partial victories from a federal judge.
Judge Joshua D. Wolson in the U.S. District Court in Delaware ruled January 4 that Wirtgen America did not infringe on two of Caterpillar’s claims on one of its patents. He also ruled that Caterpillar did not infringe on one claim on one of Wirtgen’s patents.
That leaves the remaining claims left for a jury to decide. The judge determined that because both companies’ experts offered conflicting testimony, he could not rule on the other claims being considered.
The legal battle began in 2017 when Wirtgen sued Caterpillar claiming infringement on 13 of its patents. Caterpillar countersued, alleging Wirtgen infringed on three of its patents.
Since then the case has been heard by the U.S. International Trade Commission, which ruled in 2019 that Caterpillar infringed on three Wirtgen patents. Wolson, however, ruled that was not enough for him to issue a decision. “The ITC’s decision is not factual evidence,” he wrote. “It is, instead, a decision that weighs evidence and applies the law.”
Wirtgen America’s Claims
Germany-based Wirtgen, now owned by John Deere and with North American headquarters in Tennessee, alleges that Caterpillar bought two Wirtgen milling machines, a W 210i and a W 120, which it took apart and analyzed. Caterpillar then began importing Cat PM600 Series, PM800 Series and PM300 Series models into the U.S. that contained Wirtgen’s patented devices that are found on its milling machines and recyclers, the suit alleges.
The patents include the following:
(Note: Only the last three digits of the nine-digit patent numbers are presented.)
- Patent 309 – Floating mount on front and rear axle, increasing height an obstacle can be ridden over by only one wheel. Related: Patent 316
- Patent 641 – Reverse travel shutoff feature. Monitoring device that senses the distance between the milling drum and the ground, and when the machine is traveling in the same direction of the rotation of the milling drum, it triggers a safety mechanism to prevent contact of the milling drum with the ground surface.
- Patent 592 – Measuring device to regulate the height-adjustable lifting columns. Related: Patents 871 and 530
- Patent 788 – Leveling system to sense and control milling depth and/or slope. Related: Patents 932 and 474
- Patent 268 – Drivetrain mounting and arrangement that reduces the transmission of vibrations from drivetrain components.
- Patent 972 – Controller and sensors that control the extension and retraction of one or more lifting columns to maintain the machine frame parallel to the ground or to position the machine frame at a predetermined milling level.
- Patent 390 – Sensors and control systems that automatically control milling depth and/or transverse or longitudinal inclination of the machine frame. Related: Patent 391
Caterpillar denies any infringement on Wirtgen’s patents and makes infringement claims of its own for three of its patents:
- Patent 995 – System that maintains the milling machine’s track directions when pivoting between retracted and extended track positions.
- Patent 538 – Methods and systems that adjust engine speed based on the engine load, and adjust gear ratio of the variable transmission based on the engine speed and the desired rotor speed.
- Patent 618 – Water spray system.
Judge Wolson’s ruling rejects two of Caterpillar’s claims that Wirtgen infringed on its 618 patent for its water spray system.
He rejects one of Wirtgen’s claims that Caterpillar infringed on its 641 patent for a reverse-travel shutoff feature.
All of the claims Wolson could not make a summary judgement on, due to conflicting expert opinions, would need to be decided by a jury, he wrote. A trial date has not yet been set.
Both companies seek damages as deemed by the courts, as well as the blocking of any sale, import or distribution of products that are deemed to have been infringed upon.