Vector Corporation v Glatt Air Techniques Inc

For added matter, the court must compare the application as filed with the proposed amendment through the eyes of the skilled addressee. The comparison is strict. Relevant subject matter must be clearly and unambiguously disclosed, expressly or implicitly; the inquiry is not one of obviousness.

An expressly disclosed alternative may be claimed without importing every feature of the preferred embodiment. However, a claim creates an unallowable intermediate generalisation where it combines that alternative with a feature disclosed only in a different context. Post-trial reformulation of a patent claim is exceptional and should be refused where it would require a fresh trial.

Vector Corporation sought revocation of Glatt’s European patent. Glatt applied unconditionally to amend it. Lewison J allowed the amendments and rejected the validity attacks in [2006] EWHC 1638 (Ch), [2007] RPC 12.

Vector appealed only the allowability of proposed new claim 13. The claim concerned a fluidised-bed processor in which a gas stream shielded the initial spray pattern. The central issue was whether the requirement that the means forming that stream be within the upbed introduced added matter as an unallowable intermediate generalisation.

1. Appeal allowed. The court disallowed proposed claim 13 and refused Glatt any further opportunity to reformulate it. The existing claims 1 to 12 remained.
2. Article 123(2) of the European Patent Convention and section 76(3)(a) of the Patents Act 1977 have the same meaning. The added-matter inquiry is a strict comparison between the application as filed and the proposed amendment, viewed through the skilled addressee’s common general knowledge. The question is whether the amendment teaches anything relevant to the invention which was not clearly and unambiguously disclosed, expressly or implicitly. It is not an obviousness inquiry.
3. The specification expressly presented an air wall or stream as an alternative to the cylindrical physical shield in the preferred embodiment. It therefore disclosed the concept of a Wurster arrangement in which a gas stream alone shielded the nozzle. A claim to that alternative was not, without more, an intermediate generalisation.
4. Claim 13 nevertheless required the means which formed the shielding gas stream to be located within the upbed. The application disclosed an in-upbed means for the preferred physical-shield arrangement, but did not disclose that location for the alternative air-wall arrangement. The claim thus extracted a feature from one context and combined it with another without express or implicit disclosure. That was an unallowable intermediate generalisation.
5. The patentee’s requested deletion of the offending words would amount to a post-trial claim reformulation. Applying Nikken v Pioneer [2005] EWCA Civ 906, the court held that the exceptional course of permitting such an amendment was unavailable. The revised claim could raise a substantial new sufficiency dispute and would require a fresh trial. The Court of Appeal therefore refused leave to reformulate.

• Court of Appeal (Civil Division) — allowed Vector’s appeal and disallowed proposed claim 13.
• High Court, Chancery Division, Patents Court — Lewison J allowed Glatt’s amendments, rejected the validity attacks, and granted permission to appeal on amendment issues: [2006] EWHC 1638 (Ch), [2007] RPC 12.