JC Bamford Excavators Limited v Manitou UK Limited & Anor

A longitudinal load moment control system does not inherently require a rear-axle load sensor. It may sense a predetermined safety limit by measuring arm position against a predetermined working envelope, as well as by calculating actual tipping moment. Where a patent claim requires disabling the control system so that actuators can be operated at will, switching from one qualifying control system to another does not satisfy that requirement if the replacement system continues to restrict actuator movement. The issue is resolved by purposive construction of the claim in light of the patent specification.

J.C. Bamford Excavators appealed against the finding that claim 1 of EP (UK) 2 263 965 was invalid for lack of inventive step over the Aichi patent application. The appeal followed the High Court’s judgment in [2022] EWHC 1724 (Pat). The parties had settled the wider patent proceedings, but JCB continued this appeal concerning validity of EP 965.

It was accepted that applying Aichi’s control system to a telehandler would be obvious. The central questions were whether Aichi’s working range limitation device was a longitudinal load moment control system within claim 1, and whether switching from Aichi’s moment limitation device to that device amounted to disabling the claimed control system.

Appeal allowed. Lord Justice Birss gave the judgment, with Lady Justice Elisabeth Laing and Lord Justice Nugee agreeing. The order for revocation of EP 965 was overturned.

1. The expression longitudinal load moment control system did not require a rear-axle load sensor. Although such sensors were routinely used, the common general knowledge showed that other methods could also be used.
2. The requirement that a predetermined machine longitudinal instability be sensed meant that the control system had to sense when a predetermined safety limit or threshold associated with the risk of longitudinal instability had been reached. The limit could concern rear-axle load or arm position. The claim did not require the system to sense instability itself.
3. Aichi’s working range limitation device measured the arm’s position and compared it with a predetermined working range based on the rated load or last measured load. It therefore sensed a predetermined safety limit and was an LLMC within claim 1. Both the moment limitation device and the working range limitation device fell within the claim.
4. The disablement feature had to be construed purposively in light of paragraph [0037] of the patent. Its purpose was to permit the operator to operate the actuator devices at will when travelling above the threshold speed. Switching from one LLMC to another did not satisfy that requirement because an LLMC remained in operation and continued to restrict actuator movement.
5. Although Aichi disabled the moment limitation device when the vehicle began moving, its working range limitation device then operated. Aichi therefore did not disclose disabling the LLMC required by claim 1. Claim 1 was not invalid over Aichi.

• Court of Appeal (Civil Division): Appeal allowed. Claim 1 of EP 965 was held not to be invalid over Aichi and the revocation order was overturned.
• High Court of Justice, Patents Court: HHJ Hacon held, in [2022] EWHC 1724 (Pat), that three of four patents were invalid, including EP 965, while another patent was valid and infringed in specified configurations.