Storage Computer Corp & Anor v Hitachi Data Systems Ltd

For patent obviousness, the state of the art is the material against which the claim must be assessed. An acknowledgement in a patent that earlier disclosure contains the pre-characterising features may provide a sufficient starting point, although any challenge to that acknowledgement requires evidence. The court should identify the inventive concept, the differences from the state of the art, and whether those differences would have been obvious to the skilled person without knowledge of the invention. Common general knowledge may include known concepts in combination even where the cited document does not apply them to the precise claimed system. Applying caching and intelligent scheduling concepts to a known fault-tolerant disk array required only implementation within ordinary skilled competence. Appeal dismissed.

Storage Computer Corporation and Storage Computer UK Limited appealed from a Chancery Division judgment in which Pumfrey J held that the patent was not infringed and that claims 1 and 2 were invalid for obviousness: [2002] EWHC 1776 (Ch).

After judgment, the parties settled. Hitachi agreed not to participate further but did not consent to the appeal being allowed. The appeal challenged both infringement and validity. The central issues were whether the judge had used the correct state-of-the-art starting point and whether the claimed caching and intelligent-operation features involved an inventive step.

1. Disposition. The appeal was dismissed. Because Hitachi did not participate in the appeal, the Court considered that it would be inappropriate to allow the appeal without full argument on the difficult technical issues. An amicus could not adequately substitute for instructed counsel. Once the claims were held invalid for obviousness, there was no need to decide whether Hitachi’s device infringed claim 1. There was no order as to costs.
2. Statutory framework. Under section 1(1)(b) of the Patents Act 1977, a patent requires an invention involving an inventive step. Section 3 requires obviousness to be judged having regard to matter forming part of the state of the art. The Court accepted that statutory approach.
3. State of the art. The Court rejected the submission that Hitachi had abandoned reliance on Timsit and Ouchi. The patent acknowledged that Timsit disclosed the pre-characterising features of claim 1, and that acknowledgement provided a foundation for an obviousness argument starting from that prior art. If Storage disputed the adequacy of the acknowledgement, it had to lead appropriate evidence.
4. Obviousness analysis. The Court agreed with the judge that the structured approach in Windsurfing International Inc v Tabur Marine (Great Britain) Ltd [1985] RPC 59 at 73 should be used. The inventive concept was that called for by claim 1. The differences from the prior art were its characterising features. The question was whether those differences would have been obvious to the notional skilled person without knowledge of the invention.
5. Application. The evidence established that the concepts in IBM 1, individually and in combination, formed part of common general knowledge, although IBM 1 did not apply them to a disk array or disclose parity generation and updating. Applying those concepts to the known storage system involved further intelligence, but its implementation was within the competence of the skilled person. The judge was therefore entitled to find claims 1 and 2 obvious. Applying the appellate caution identified in Biogen Inc v Medeva Plc [1997] RPC 1 at 45, the Court found no sufficient basis to disturb that evaluation.

• Court of Appeal (Civil Division) — dismissed the appeal from the Chancery Division judgment. The validity conclusion was upheld; infringement was not decided.
• Chancery Division — Pumfrey J held that the patent was not infringed and that claims 1 and 2 were invalid for obviousness: [2002] EWHC 1776 (Ch).