Disclosure is a powerful tool in patent litigation

The disclosure process under English law creates powerful opportunities during patent litigation. Careful use of disclosure can reduce costs and speed up proceedings across Europe, as shown in recent litigation between Danisco and Novozymes.

What is disclosure?
During patent litigation under English law, both the claimant and defendant are often obliged to disclose information which adversely affects their own case or supports the other party’s case. A party may request disclosure – and doing so may allow access to information held by another party which would otherwise be unavailable. 

Not all disclosed documents can be inspected by the opposing party – for example, some will be protected by legal privilege. In patent cases, disclosure is usually limited to documents which were created two years before or after the claimed priority date of the patent, but the court has discretion to waive this requirement where appropriate.

The principle underlying disclosure is that the parties should be aware of information which is relevant and could reasonably be provided by the other parties. In the absence of disclosure, parties could benefit by withholding relevant information. 

The process of requesting information during litigation is known as "disclosure" under English law, whereas the US courts have a similar (although more wide-ranging) process known as "discovery". 

A party may request disclosure if it suspects that relevant information is being withheld and a court may sometimes specifically require information to be disclosed. A request for disclosure is assessed by the courts following a balancing of the need for disclosure with the needs of the party that is being asked to provide the new information. 

How widely can the information be used?
Disclosed documents are not available to use automatically in other proceedings without permission from either the party that disclosed them or the court that ordered disclosure. 

However, a document made available by using disclosure in the United Kingdom may change the outcome of the case across Europe. Recently, in Danisco v Novozymes, documents made available using litigation in England were used to help revoke Novozymes’s patent across Europe.   

Danisco v Novozymes
Novozymes’s patent claimed a method for making animal feed which contained useful enzymes. Danisco applied for revocation of the patent and alleged that Novozymes’s method was obvious because it provided no improvement over known methods. Novozymes disagreed and argued that its method was not obvious because the method increased the stability of the enzymes.

Novozymes’s patent included a number of examples which showed that its patented method did provide improved enzyme stability. Danisco appears to have suspected that the patented method would not always work, and that the results presented by Novozymes had been “cherry picked” to avoid publishing negative results. 

It seems that Danisco suspected that Novozymes had tested the patented method extensively, as Novozymes was planning to launch a product made using the patented method in the near future. Therefore, Danisco requested disclosure of experiments conducted by Novozymes when testing its patented method, which Novozymes eventually provided.

As Danisco expected, Novozymes’s results showed that sometimes the patented method provided improved enzyme stability and sometimes it did not. This finding was important, as in order to argue that a new method is not obvious because it provides an improvement, the improvement should occur reliably and not just in certain specific circumstances. 

As Novozymes’s negative results showed that the improved enzyme stability did not always occur with the patented method, Danisco hoped that the courts would decide that the method was obvious. 

Danisco’s strategy
Danisco was attempting to revoke Novozymes’s patent in the United Kingdom, Germany, Denmark and the Netherlands, as well opposing it centrally at the European Patent Office (EPO). 

The EPO acts as a central patent granting authority for Europe and a European opposition can lead to the patent being revoked in all European states. Therefore, Danisco decided to try to use Novozymes’s negative results to support its opposition at the EPO.

However, in order to use Novozymes’s negative results in the EPO, Danisco needed permission from the English court. The court initially refused to release the negative results, but reversed its position when the hearing date for the trial was delayed by Novozymes to fall after the final hearing at the EPO.

Thanks to the evidence from disclosure, the EPO considered that the patented method was obvious, in part because the improved enzyme stability did not always occur with the patented method, and therefore the patent simply claimed an obvious alternative method. The patent was revoked by the EPO, which automatically led to revocation in the United Kingdom, Germany, Denmark and the Netherlands. 

Key points
In Europe, only the United Kingdom has a comprehensive system for requiring disclosure of relevant documents during patent litigation, so it may be useful to start proceedings in the United Kingdom specifically to obtain access to certain documents. 

Where a business believes that a competitor is in possession of information which damages that competitor’s position, an action in the United Kingdom might allow access to this information. Once useful information has been identified using disclosure, the opposing party can request permission to use this information in other jurisdictions.   As a result, actions in the United Kingdom can affect the course of proceedings in other jurisdictions.

A business may decide to identify documents which could become available to competitors due to disclosure in the United Kingdom in order to brief its legal team accordingly. Novozymes’ representatives at the EPO made statements which were said to be contradicted by the negative results which emerged as a result of the disclosure in the English courts. 

Disclosure through the English courts creates powerful opportunities during litigation, especially patent litigation.  These opportunities can be important when there is litigation in multiple jurisdictions, as the information disclosed in the English courts may sometimes be used in other jurisdictions.

This is an Insight article, written by a selected partner as part of IAM's co-published content. Read more on Insight

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