Icescape Ltd v Ice-World International BV & Ors

Priority under the European Patent Convention is available only where the skilled person can derive the claimed subject matter directly and unambiguously from the priority document as a whole. Common general knowledge informs the reading of that document but cannot supplement an omitted feature.

Patent infringement requires first a purposive construction of the claim and then, if necessary, a separate inquiry into equivalents. A variant infringes where it achieves substantially the same result in substantially the same way, this would be obvious to the skilled person, and strict compliance was not intended to be essential. Patent-file history is exceptional evidence and must unambiguously resolve a genuinely unclear issue or be required in the public interest.

Icescape Ltd operated a mobile ice rink with foldable pipe joints. Ice-World International BV owned a patent for a cooling member for mobile ice rinks and alleged infringement. It also sent Icescape and its customers letters alleging infringement.

Icescape sought relief for groundless threats, revocation of the patent and a declaration of non-infringement. The Patents Court held that the patent was not entitled to priority and was invalid, that Icescape did not infringe, and that Ice-World had no defence to the threats claim: [2017] EWHC 42 (Pat).

Ice-World appealed on priority, infringement, and its statutory defence to unjustified threats. The central issues were whether common general knowledge could supply omitted priority features, whether a parallel manifold connection infringed by equivalence, and whether Ice-World lacked knowledge or reason to suspect invalidity when making the threats.

1. Appeal dismissed. The patent was not entitled to priority and was therefore invalid. The priority document did not expressly or implicitly disclose the multiple elements and fluid-tight manifold connections required by features A, D and E of claim 1. The skilled person could use common general knowledge to understand the document, but not to add a feature which the document did not directly and unambiguously disclose. That conclusion followed the strict priority approach in Same Invention, G2/98.

2. The court nevertheless allowed the infringement ground. On a purposive construction, features D and E required adjacent manifolds to be connected in series. However, applying Actavis UK Ltd v Eli Lilly & Co, [2017] UKSC 48, a parallel connection was an immaterial variant. The patent’s inventive core was the fluid-tight flexible joint which allowed rigid pipe sections to fold for transport. The parallel connection achieved substantially the same result in substantially the same way. It would have been obvious to the skilled person that it did so, and the skilled reader would not have treated strict compliance with the series connection as essential.

3. Reference to the prosecution history could not alter that conclusion. The file did not unambiguously resolve the scope of claim 1, nor would its exclusion offend the public interest. It therefore fell below the exceptional threshold stated in Actavis UK Ltd v Eli Lilly & Co, [2017] UKSC 48.

4. Ice-World failed to establish the defence in section 70(2A)(b) of the Patents Act 1977. It called no evidence from the individuals responsible for the threats and gave no adequate evidence of their knowledge or understanding. Its patent-attorney advice did not address priority and its underlying instructions were not disclosed. Ice-World had therefore not shown that it neither knew nor had reason to suspect the patent’s invalidity.

• Court of Appeal (Civil Division): dismissed Ice-World’s appeal. It upheld the findings on lack of priority, invalidity and the failure of the threats defence, while reversing the finding of non-infringement.
• High Court, Patents Court: held the patent invalid for lack of priority, found no infringement, and held that Ice-World had no defence to the groundless-threats claim under section 70(2A) of the Patents Act 1977: [2017] EWHC 42 (Pat).