Zipher Ltd v Markem Systems Ltd & Anor

An injunction enforcing an undertaking must reflect the undertaking’s proper construction. It should be neither wider nor narrower than the obligation undertaken, so that the party bound need consult only one instrument when assessing the legality of its conduct.

Where an undertaking was given to narrow the scope of a patent monopoly, it may require positive amendment of pending applications and granted patents, and may also prohibit the filing or assertion of claims which cannot be amended. The obligation may extend to foreign patents and applications where the surrounding context shows that the undertaking was intended to cover the relevant international application and its derivatives.

Following an earlier judgment in the claims between Zipher Ltd and Markem Systems Ltd, the court adjourned argument on the form of order. Zipher had given an unconditional undertaking concerning the scope of claims deriving from a UK patent application and an international patent application.

The court was asked to determine the scope of an injunction supporting that undertaking. The issues concerned substitution for the undertaking, the mandatory and prohibitory elements of the injunction, its territorial scope, and the method of identifying the relevant patent claims.

1. The injunction had to be construed by reference to the undertaking. It was to be neither wider nor narrower than the undertaking properly construed. The question whether the undertaking should formally be discharged was therefore moot, since compliance with the injunction would avoid breach of the undertaking.

2. The undertaking was not merely an undertaking not to assert patent rights against Markem. Its purpose was to cut down the scope of the monopoly. It therefore justified an injunction requiring Zipher to take all steps within its power to amend relevant pending applications and granted patents. It also justified prohibitions on filing or asserting claims which could not be amended.

3. The court declined to require Zipher to disclaim or disavow unamendable claims, since the content of that obligation was uncertain, particularly in foreign jurisdictions. A prohibitory injunction was the appropriate corollary.

4. The undertaking was not confined to UK patents. The context, including the dispute over entitlement to the international application and the parties’ treatment of the UK and international applications as corresponding instruments, showed that it extended to patents and applications deriving from or based on the international application.

5. The relevant claims were claims to a push-pull type tape transport mechanism for printers, including corresponding printer and method claims. The restriction applied wherever the relevant mechanism appeared in the claims hierarchy. Zipher could not avoid the undertaking by combining claims 1 or 4 with another feature.

6. An injunction was granted, subject to drafting corrections, in terms requiring amendment of relevant claims to include all the features of claims 1, 4 and 5 of the UK application, and restraining filing or assertion of claims lacking those features.

The judgment followed an earlier judgment in the same proceedings delivered on 25 June 2008. The present judgment determined the scope of the injunction and related final-order issues.