Trade

Application to amend patents - whether covetous - court to consider draftsman's bona fide assessment of prior art at time of drafting specificationKimberly-Clark Worldwide Inc v Proctor & Gamble Ltd and Another: ChD (Pumfrey J): 21 July 2000

The judge dismissed the claimants' action against the defendants claiming infringement of patent no.

EP (UK) 0297110, which was titled 'absorbent material' and concerned diapers and incontinence aids, and revoked the patent on the ground of its obviousness.

The claimants sought to amend the patent, which application was opposed by the defendants on the basis that the amendment was covetous.

Anthony Watson QC and Thomas Mitcheson (instructed by Bristows) for the claimants.

Simon Thorley QC and Colin Birss (instructed by Simmons & Simmons) for the defendants.

Held, dismissing the application to amend, that an allegation of covetousness could not be made out unless it was first established that the draftsman of the specification had sought to obtain a claim of a breadth which was unjustified on the material available to him, including the description of the invention and such information as he had concerning the prior art; that the court should not substitute an assessment made ex post facto in the light of material, the significance of which the draftsman had, in good faith, failed to appreciate, for the draftsman's bona fide assessment of the breadth of protection which he could obtain in the light of the prior art; that standards applicable to the drafting of a domestic UK application should not be applied without examination to an application which started life in the United States and was prosecuted to grant in the European Patent Office by a German firm of patent attorneys without any reference to British practice; but that whilst there were no grounds upon which the proposed amendment should be refused, the patent as proposed to be amended would remain invalid.