Patents: disclosure of documents relating to obviousness

06 July 2016

Audrey Horton

The High Court, in an action for revocation and declaration of non-infringement of a patent, has refused to order the patent owner to give disclosure of documents related to validity.


Civil Procedure Rule (CPR) 31.5 sets out six options for disclosure of documents including standard disclosure, as well as issue-based disclosure and orders dispensing with disclosure. In relation to patents standard disclosure does not require the disclosure of documents that relate to any ground on which the validity of a patent is put in issue, except documents which came into existence within the period beginning two years before the earliest claimed priority date, and ending two years after that date (paragraph 6.1(2), Practice Direction 63) (paragraph 6.1(2)).


P brought an action for revocation of H’s patent and for declarations of non-infringement in respect of robotic lawn mowers that P manufactured, claiming that the patented invention lacked novelty or was obvious. Before the case management conference (CMC), H provided a disclosure report which stated that disclosure on validity would be produced in accordance with paragraph 6.1(2). Later, H argued that no validity disclosure should be ordered.

P argued that H should still give disclosure on obviousness because knowledge of the inventor’s experiments could assist an applicant for revocation to determine whether the steps actually taken by the inventor were steps that an ordinary skilled person would or could take, and whether they would or should have been obvious. Also, any knowledge acquired regarding the inventor’s experiments or researches could be used in cross-examination of H’s technical expert by reference to what the inventor did.


The court held that no disclosure from H in respect of validity should be ordered.

Obviousness was an objective issue. The notional person skilled in the art knew more but foresaw less than real skilled people. Therefore, evidence of what the inventor actually did was often of little value and there was always a risk of hindsight. To establish that this evidence was probative could result in a dispute about how similar the inventor was to the person skilled in the art. This sort of evidence was secondary evidence as distinct from the primary evidence consisting of the opinions of expert witnesses.

CPR 31 emphasised the overriding objective and the need to limit disclosure to that which was necessary to deal with the case justly. The effect of CPR 31.5 was that standard disclosure was not the default option any more but one of six options. The Chancery Guide also states that careful consideration should be given to the alternatives to standard disclosure.

The 2013 reforms removing the prima facie rule in favour of standard disclosure did not mean that a party seeking an order for some disclosure had a difficult burden to discharge but meant the court had to have a basis for that selection. The selection of the correct approach was governed by the overriding objective to deal with cases justly and at proportionate cost.

Here, the question of whether to order standard disclosure was in substance the same as whether to order disclosure on obviousness on an issue-by-issue basis. It was common ground that disclosure on infringement should be given. The only other existing issue was validity, specifically obviousness, so any disclosure on this issue would be standard disclosure.

The court considered whether it would be in accordance with the overriding objective to order standard disclosure. Proportionality would be important and two major considerations were the likely probative value of the material that could be produced and the cost of doing so, in the context of the proceedings as a whole. The question depended on fairness and the interests of justice.

The case was neither of very low nor very high value. Based on cost budgets, the likely costs would not swamp the value of the dispute. The likely cost of the obviousness disclosure was not a very substantial aspect of the overall costs but neither was it a trivial sum.

H had confirmed that it was not planning to rely on anything that might require express disclosure, such as commercial success or calling the inventor as a witness. If H showed its own documents to its expert, the expert’s report was required to state that and then production of those documents and disclosure on the issue would be ordered. In the meantime, the court would not order disclosure on obviousness.


Controlling the scope and amount of disclosure has been an important part of the reforms of civil procedure in general, including patent litigation. This decision emphasises the need for the party seeking an order for disclosure to show that it is likely to result in useful and relevant material. In reaching this decision, it is likely that the High Court was influenced by the success of the Intellectual Property Enterprise Court (IPEC) and its specific cost-benefit analysis procedures. In the IPEC, a party has no automatic right to any disclosure. Instead disclosure is dealt with at the CMC on an issue-by-issue basis in accordance with the overriding objective and proportionality, balancing the likely probative value of the documents against the cost or difficulty of the search. It may also be more aligned with the likely approach to disclosure of the Unified Patent Court.

Case: Positec Power Tools (Europe) Ltd and others v Husqvarna AB [2016] EWHC 1061 (Pat).

First published in the July 2016 issue of PLC Magazine and reproduced with the kind permission of the publishers. Subscription enquiries 020 7202 1200.