Zipher Ltd v Markem Systems Ltd

A patentee may commence infringement proceedings relying on claims proposed in an application to amend, even where it accepts that relevant claims as granted are invalid. An amendment allowed under section 75 of the Patents Act 1977 operates retrospectively, and section 76 prevents the amended claims from enlarging the protection conferred. The claimant therefore asserts an existing legal right where the patent is partly valid, although relief cannot be granted unless and until amendment is allowed. CPR 63.10 expressly contemplates applications in which the patentee does not contend that the pre-amendment claims are valid. The court should avoid a procedural rule that discourages timely admissions and requires separate proceedings before related issues can be heard together.

Zipher brought infringement proceedings against Markem concerning a patent for a printer drive mechanism. The pleaded infringement relied on claims proposed in Zipher’s pending application to amend the patent, while Zipher accepted that some granted claims were invalid. Markem applied to strike out the claim, arguing that Zipher had no present cause of action because amendment remained discretionary and had not yet been allowed.

The central issue was whether proceedings could be brought in those circumstances, or whether Zipher had first to obtain amendment of the patent through the Patent Office.

1. Application refused. Zipher was entitled to bring the infringement claim. Relief would not be granted before amendment was allowed, if it was allowed, but that was different from whether Zipher could approach the court at all.
2. A cause of action is a factual situation which entitles one person to obtain a remedy against another. If a patent remains wholly invalid, no cause of action arises. However, a patent which is partly invalid is also partly valid, and section 63 of the Patents Act 1977 recognises that relief may be granted in respect of a partially valid patent.
3. Under sections 75 and 76 of the Patents Act 1977, an allowed amendment is retrospective and cannot extend the protection conferred by the patent. Infringement of the amended claims would therefore necessarily involve infringement of the patent as granted. The possibility that amendment might be refused did not prevent a retrospective cause of action from arising.
4. The principle concerning unfair advantage identified in Smith, Kline and French Laboratories Ltd v Evans Medical Ltd [1989] FSR 561 was not a rigid rule. It was directed to threats made in reliance on claims known to require amendment. Pleading by reference to the granted claims to identify the alleged infringement, while stating that only the proposed amended claims would be relied on, was permissible.
5. CPR 63.10, and the observations in Nikken Kosakusho Works v Pioneer Trading Company [2006] FSR 4, supported the conclusion that the procedural rules contemplate amendment applications where the patentee accepts that the original claims are invalid. Requiring a separate Patent Office procedure first would create delay, cost and an incentive against timely admissions.
6. The defendant was ordered to pay £9,000 for the claimant’s costs of the application. Permission to appeal was granted. Directions were made for the amendment application and main action, with costs of the amendment application reserved and other costs in the case.

First-instance decision. No earlier decision in the same proceedings is identified as the decision under appeal.