David J Instance Ltd & Anor v Denny Bros Printing Ltd & Anor

An appellate court should not interfere with a trial judge’s assessment of obviousness, an evaluative question involving the application of a legal standard to facts, unless there is an error of principle. The structured approach in Windsurfing International Inc v Tabur Marine (GB) Ltd is useful but not mandatory. The essential question is whether the skilled person, using the common general knowledge and the prior art, would regard the claimed step as obvious. Where known design features leave only a small number of evident combinations, selecting one such combination may lack inventive step. Once a non-stick patch was obvious, its placement and application by unspecified printing were also obvious.

The appellants challenged the Chancery Division judgment of Laddie J, which had found claims 6, 7, 10 and 11 of European Patent (UK) 0628941 invalid for obviousness and had revoked the relevant patents. The appeal concerned claim 6, relating to a leaflet label combining the known Kleerform multiple-footprint construction with an offset base label, and claims 7 and 10, relating to creating an easy-release tab by applying a non-adhesive patch and printing it onto release material.

The central questions were whether the judge had applied the correct approach to obviousness, whether he had assessed common general knowledge without hindsight, and whether his evaluation of the evidence and prior art disclosed any error of principle.

1. Appeal dismissed. The Court of Appeal, comprising Aldous LJ, Rix LJ and Lloyd J, upheld the findings that claims 6, 7 and 10 were obvious. The remaining patents were consequently invalid and subject to revocation.
2. Obviousness is an evaluative question. An appellate court should review the trial judge’s conclusion in accordance with the approach stated in Designers Guild Ltd v Russell Williams (Textiles) Ltd, and should not reverse it merely because the appellate judges might form a different impression. Intervention requires an error of principle.
3. The structured analysis associated with Windsurfing International Inc v Tabur Marine (GB) Ltd is useful, but it is not essential in every case. A judge may proceed directly to whether the invention was obvious, provided that the judge adopts the mantle of the skilled person and asks the correct question.
4. For claim 6, the inventive concept was the offset base-label feature added to the Kleerform label. The skilled person would understand that the Kleerform’s two adhesive footprints were essential to its operation. Because base labels were known and some customers required them, the skilled person would consider how to retain the Kleerform advantages while incorporating a base label. The two resulting constructions, including the claimed offset arrangement, were obvious.
5. The judge had adequately assessed common general knowledge and had not relied on hindsight. The absence of earlier commercial adoption did not establish a long-felt want, since the evidence did not show a significant unmet problem or pent-up demand.
6. Claims 7 and 10 were also obvious. Once the use of a non-stick or stick-defeating patch was obvious, there was no invention in selecting either of the two evident locations. Applying the patch by unspecified printing with unspecified ink was likewise an obvious general concept, even if other methods might have been tried first.
7. The appeal was dismissed with costs, including the respondent’s notice. Payment on account was ordered, and permission to appeal was refused, subject to the stated stay concerning revocation.

• Court of Appeal (Civil Division): Appeal from the Chancery Division judgment of Laddie J dated 14 April 2000. Appeal dismissed.