Supponor Limited & Anor v AIM Sport Development AG

Patent claims are construed through the eyes of the skilled person using the common general knowledge. Limitations cannot be read into broad claim language merely because the specification’s examples use a narrower technique. The inventive concept normally follows from the properly construed claims and cannot restrict them.

Thus, “image property” may include pixel-by-pixel brightness analysis where the claim does not require higher-order processing. A frequency-selective detection claim may cover a system detecting radiation emitted by the display board if the claimed filtering concerns only the frequencies used to display the moving image. An amendment requiring the screen to appear inactive may produce a different result. A case-management concession about one claim does not automatically invalidate another.

The respondent was the patentee of EP (UK) 3 295 663, concerning digital replacement of advertising images on sporting-event broadcasts. The appellants relied on their earlier patent application, WO 2013/186278 A1, known as Nevatie. At trial, Meade J held claim 12 valid and infringed, and allowed amendments as a precaution: [2023] EWHC 164 (Pat).

The appeal raised six grounds concerning claim construction, pixel-by-pixel processing, dark-on-light methods, infringement, obviousness, a purported admission concerning claim 1, and amended claims. The central issues were whether unamended claim 12 covered the Nevatie approach, whether amended feature 12.7 excluded it, and whether abandoning claim 1 affected the defence of claim 12.

Lord Justice Birss gave the leading judgment, with Lord Justices Phillips and Males agreeing. The appeal was dismissed. Ground 2 succeeded, but the amendment to claim 12 was upheld and the final order was to reflect it.

1. Construction. Claims are construed through the skilled person’s eyes, with the common general knowledge. Matter neither set out in the patent nor part of that knowledge is irrelevant to construction. Hypothetical examples and consequential arguments cannot assist without an evidential foundation. Limitations absent from the claim cannot be imported from examples in the specification. The inventive concept normally follows from the properly construed claims and cannot be used to narrow them.
2. Pixel-by-pixel processing. “Image property” is a broad expression. The claim was not confined to higher-order processing or consideration of neighbouring pixels. The specification’s examples were permissive and did not impose those limitations. Pixel-by-pixel analysis could therefore fall within claim 12. Ground 1 failed.
3. Unamended claim. The word “detecting” did not distinguish between detecting a dark object against a bright background and detecting a bright object against a dark background. The frequencies required to be filtered were those emitted by the display board to show the moving image. Nevatie’s IR camera detected the bright IR emitted by the board, and its failure to filter that IR did not matter. The relevant Nevatie method therefore fell within unamended claim 12, subject to the separate moving-image issue. Ground 2 succeeded.
4. Amended claim. In feature 12.7, “active” referred to the board’s capability to emit light, not to whether the displayed image was moving. The requirement that the screen appear uniform and monotone as if inactive excluded Nevatie, whose IR detection image showed the board actively emitting IR. Ground 6 failed. The infringement finding was also upheld, and ground 3 failed. The Nevatie-OD obviousness ground did not affect the outcome because the amended claim excluded a system showing an active IR board.
5. Admissions. AIM had not admitted that claim 12 was invalid. Its proposal concerned case management and expressly maintained claim 12. Even an admission that a product claim was invalid would not automatically establish invalidity of a materially different method claim. Any invalidity attack based on admitted facts would still require proof, and the ground of invalidity would matter. Ground 5 failed. [2021] EWHC 2021 (Pat) did not decide a relevant issue of principle.
6. Draft judgment. The court applied the guidance in R (Mohamed) v Foreign Secretary (No 2) [2010] EWCA Civ 158 and Egan v Motor Services [2007] EWCA Civ 1002. Draft circulation permits correction of typographical and similar errors; reargument is exceptional and requires prompt notice to the other party. The post-judgment submissions did not justify reopening the decision. No respondent’s notice was required on the amendment issue because Supponor had raised it on appeal.

1. Court of Appeal (Civil Division): Appeal dismissed. Ground 2 was allowed, but the amendment to claim 12 was upheld and the order was directed to reflect that amendment.
2. High Court of Justice, Patents Court: Meade J held claim 12 valid and infringed, allowed the proposed amendments as a precaution, and rejected the appellants’ arguments on construction, infringement and the Promptu point: [2023] EWHC 164 (Pat).