JC Bamford Excavators Limited v Manitou UK Limited & Anor.

For inventive step, the court should identify the skilled person and common general knowledge, identify the inventive concept of the claim, compare it with the prior art, and ask whether the differences would have been obvious without hindsight. The inventive concept is that of the claim in issue, stripped of unnecessary verbiage. A prior-art document must be read with interest, even where it comes from another technical field. Long-felt want may support inventiveness only where the absence of the invention has no plausible explanation other than non-obviousness. For infringement by equivalents, the Actavis reformulated questions are guidelines and focus on the inventive concept.

JCB alleged that Manitou’s telehandlers infringed four patents concerning safety control systems for load-handling arms. Manitou counterclaimed for revocation on grounds including lack of inventive step and insufficiency.

The court considered EP 065 and GB 595, concerning a soft-stop control; EP 965, concerning disabling longitudinal load moment control above a travelling-speed threshold; and EP 382, concerning a threshold varying with arm angle. It also considered infringement, including infringement by equivalents and a late amendment application.

1. EP 065 and GB 595. The soft-stop invention lacked inventive step over Kruger and Tadano. Each disclosed an automatic soft stop for a load-carrying arm. The skilled person would have understood that the concept could be applied to a telehandler and would have used the conventional rear-axle sensor. The age of Kruger did not establish a long-felt want because there was no evidence that the industry had considered Kruger and there were plausible commercial explanations for the absence of the development.
2. EP 965. Claim 1 lacked inventive step over Aichi I. Aichi I disclosed a longitudinal load moment control system, a motion sensor relating to travelling speed, and disablement of the moment-limitation device when the vehicle began to move. Claim 10 also lacked inventive step because the disclosed threshold was zero, which was less than 5 kph.
3. EP 382. The patent was valid. On a purposive construction, the position signal could represent the arm angle relative to the horizontal where the relationship with the machine body was substantially known or assumed. The claims covered either an abrupt stop or a soft stop, with the stopping threshold varying according to arm angle. The inventive concept was a controller more permissive at low arm angles and more restrictive at high angles by varying the moment-of-tilt threshold. GB 595 did not make that concept obvious. Tadano varied the threshold for slowing movement, but not the threshold at which the arm was stopped.
4. The insufficiency objection to EP 382 fell away because the parties agreed the skilled person would adopt the court’s construction of integer (g).
5. EP 065 and GB 595 were invalid, although configuration A machines would have infringed them. EP 965 was invalid. EP 382 was valid, admitted to be infringed by configurations A and B, not infringed by configuration C, and infringed by configuration D. A substantial late amendment to the normal-infringement case was refused because it would prejudice Manitou.