Edwards Lifesciences AG v Cook Biotech Incorporated

Patent claims must be construed as the skilled person would understand the patentee’s language in context. A stent is radially expandable if it can be delivered in a reduced form and expanded to contact and support the vessel lumen; uniform radial expansion is unnecessary. For priority, the claimant must have filed the earlier application or be its successor in title when the later application and priority claim are made. Subsequent acquisition of title does not cure the defect. Generic disclosure anticipates a specific invention only where performance of the disclosure would necessarily infringe, and the disclosure is enabling. Obviousness must be assessed without hindsight using the structured approach in Pozzoli v BDMO. The patent was invalid for obviousness, although the principal infringement case also failed.

Edwards Lifesciences AG sought revocation of European Patent (UK) 1 255 510, owned by Cook Biotech Incorporated, and denied infringement of the patent by its SAPIEN artificial heart valve. Cook counterclaimed for infringement. The validity challenges alleged lack of novelty, obviousness over several prior publications and common general knowledge, insufficiency and added matter. The principal issues included claim construction, entitlement to priority from a United States application, anticipation by Thorpe, obviousness over Andersen, Moll and Pavcnik, and infringement.

1. Construction. Applying the principles in Kirin Amgen v Hoechst Marion Roussel, the claims were construed from the perspective of the skilled team. A stent included an integral structure supporting the valve, even if it contained recognisable joined rings or units. “Radially expandable” did not require uniform expansion along radii. A valve could include non-moving pocket material, but the claim required the valve itself to be made with collagen-containing biomaterial. “Substantially” meant virtually the whole length of a stent.
2. Priority. Under section 5 of the Patents Act 1977 and Article 4 of the Paris Convention, a person could claim priority only if that person had filed the earlier application or was its successor in title when the later application and claim were made. Cook’s later acquisition of the other inventors’ rights did not cure the defect. The patent therefore had no priority date earlier than 31 January 2001.
3. Novelty. Applying Synthon v Smithkline Beecham, anticipation required an enabling disclosure which, if performed, would necessarily infringe. Thorpe’s generic reference to other mammalian tissue did not specifically and necessarily disclose pericardium. The novelty attack based on Thorpe failed.
4. Obviousness. The structured approach in Pozzoli v BDMO was applied without hindsight. Andersen made claim 1 obvious, including the use of a pericardial fabricated valve and leaflets extending substantially between the stent ends. The subsidiary claims added no inventive contribution. Moll did not make claim 1 obvious because of the practical difficulties in collapsing and expanding the device and the absence of a convincing reason to adopt pericardium. Pavcnik made claims 1, 15, 22 and 31 obvious, but not claims 3, 8, 12 or 28.
5. Other validity issues and infringement. “Substantially” was neither meaningless nor insufficient, and the added-matter objections failed. SAPIEN did not infringe claim 1 because its valve included a Dacron component and its valve and leaflets extended only about 75 per cent of the stent length.
6. Order. The patent was held invalid and not infringed. The form of order was to be addressed if not agreed.