The discovery (or disclosure) stage of patent proceedings can be a key strategic element yet burdensome part of the litigation. In Ireland, the general rules of discovery apply in relation to patent disputes as in any other case. This can be contrasted to an extent with the position in England and Wales, where provision is made in the Civil Procedure Rules for standard disclosure procedures with express modifications and limitations for patent cases. There are no such custom provisions under the equivalent Irish rules for patent matters and so case law must be referenced for guidance. This article examines the discovery procedure in Irish patent proceedings, particularly in the pharmaceutical and medical device sector, and highlights the similarities and differences with the disclosure procedure in England and Wales.

The Irish discovery procedure

Order 31 Rule 12 of the Irish Rules of the Superior Courts (as amended) provides that a party seeking discovery of documentation in proceedings must demonstrate that the documents are both relevant and necessary for the fair disposal of the proceedings and/or to save costs in the litigation. A party is only required to disclose documents that are in its “possession, power or procurement” and discovery is in the form of a list/schedule of documents attached to an Affidavit of Discovery.

Any court application for discovery must be preceded by a letter seeking voluntary discovery from the other party, which clearly identifies the categories of documentation sought and sets out detailed reasons for seeking each category. Such reasons must resonate with the requirement that the documents are relevant and necessary to the litigation. Therefore, blanket discovery is not permissible in Irish proceedings. All documentation sought by a party to the litigation must be identified and categorised in detail and reasons provided for seeking such categories before the request can be entertained either on a voluntary basis or by the Irish courts in cases of dispute. The discovery phase takes place after the pleadings in the case have closed and in patent cases will invariably form part of the case managed procedure in the Commercial Court.

As a consequence of the general nature of the Irish discovery rules, there have been a number of cases over the last few years, where the Irish courts have determined what disputed documents must be disclosed or not as the case may be in patent proceedings. In determining such issues, the Irish judiciary has endorsed the classic statement of Brett L.J. in the case Compagnie Financière et Commerciale du Pacifique v Peruvian Guano Co, where the following documentation is potentially discoverable in patent litigation:

“Every document relating to matters in question in the action, which, not only would be evidence upon any issue, but also which, it is reasonable to suppose contains information which may – not which must – either directly or indirectly, enable the party requiring the affidavit either to advance his own case or to damage the case of his adversary.”

There are three areas in particular where discovery in patent actions is relevant, namely patent claim construction, infringement and invalidity proceedings. It can be gleaned from the relevant case law that in patent cases discovery of documentation is not necessarily ordered for the broad issues of infringement and validity, but only those issues that are narrowed down by the pleadings in the case, particularly the Particulars of Infringement and the Particulars of Objection. If a matter is not pleaded then it will be difficult to justify a request for discovery as the Irish Courts consistently criticise any perceived “fishing expedition”.

Discovery in patent claim construction matters

In respect of patent construction, the Irish Supreme Court case of Ranbaxy Laboratories Ltd and others v. Warner Lambert Co., held that discovery of correspondence between the patentee’s patent agents and various patent offices in the prosecution of a patent application were not discoverable if merely sought to assist the Court in the interpretation of patent claims.

That case concerned an application by Ranbaxy for a declaration of non-infringement and both the High Court and the Supreme Court held that due to the nature of patent claim construction, which in Ireland is a purposive construction akin to the English position as set out by the House of Lords in Kirin Amgen Inc. v Hoescht Marion Roussel Ltd, the actual intention of the patentee is irrelevant. The appropriate test is from the perspective of persons to whom the patent is addressed and who are skilled in the art rather than the perspective of the patentee or inventor. Therefore, evidence of the intention of the patentee is not admissible in pure patent claim construction proceedings and it is therefore predictable that disclosure of the patent prosecution files will not be forthcoming for such purposes.

Discovery in invalidity actions

In the case of an invalidity action, however, such correspondence or files could be discoverable if, for example, the documentation demonstrated a consideration of the prior art (or lack thereof) and novelty was in issue. When a patent is the subject of a claim for invalidity based on lack of novelty or obviousness, then the inventor’s notebook could also be admissible. In the Commercial Court cases of Schneider (Europe) GmbH v Conor Medsystems Ireland Limited and Medtronic Inc. and others v. Guidant Corporation and others , the respective judges ordered discovery of the inventor’s notebook on the basis that it would assist the defendant in marshalling its own expert evidence, and cross-examining the patentee’s expert, on the obviousness issue.

The Irish Courts therefore endorsed the English decision in SKM SA and another v. Wagner Spraytech (U.K.) Ltd and others in permitting such an offensive and defensive justification for the disclosure of an inventor’s notebook. However, it will be interesting to see whether the caveat in the subsequent English Court of Appeal decision in Nichia Corpn v Argos Ltd , which held that inventor notebooks need not be disclosed as a routine, will have a bearing in future Irish cases or will it be considered a nuance between the two jurisdictions.

If an invalidity attack is based on lack of novelty then prior art is necessary to ground such a claim. In Ireland, there is also no “four year rule” as contained in the Civil Procedure Rules. As a result, there is no express temporal limitation on what documents fall inside or outside the scope of discovery of prior art documents. However, it is open to a party to Irish patent proceedings to seek in correspondence at the voluntary discovery stage, or during any court application if agreement cannot be reached, to limit the period of time for which prior art documents must be searched for and discovered.

Any discovery request for prior art documentation must be specific. For instance, in the Schneider Case a request for documents relating to all (i.e. unspecified) US patent applications concerning the product of a particular European patent and disclosing the state of the art prior to the priority date was rejected by the Court as being too vague. Miss Justice Finlay Geoghegan held that the onus is on the party seeking such discovery to identify the relevant patent before a court can make such an order otherwise the application for discovery is properly described as a “fishing exercise”.

In the Medtronic Case, an application for discovery of all documentation concerning patent applications before the Irish and European Patent Offices disclosing or claiming the product the subject of the patent was similarly rejected as not being necessary and particularly in circumstances where the patentee had already agreed to discover the entire Irish and European patent files for the patents relied upon.

It seems appropriate that a defendant in infringement proceedings that has counterclaimed for invalidity be entitled to discovery of all documents that were referenced and considered by the patentee and/or the patentee’s agents in determining the patentability of the invention at issue. Such discovery was ordered by Mr Justice Kelly in the Medtronic Case, albeit with some reservations, particularly in circumstances where the defendants had already agreed to discover all documents that would be relied upon by the defendants to attack the validity of the patent at the trial of the action. This demonstrates the tactical considerations that should be taken into account in drafting voluntary discovery request letters as certain requests, if agreed to voluntarily or ordered by the Court, could support the other side’s arguments for reciprocal categories being granted in cases of dispute.

Another example of this reciprocity concept in the Medtronic Case is where the defendants sought discovery of all documents sent to, or received from, any expert or consultant retained by the plaintiffs to evaluate any matter in issue in the case or other litigation involving the patents. The reasons given by the defendants for seeking such a category were based on the documentation assisting the defendants in ascertaining the validity of the patents because the documents indicated the views and opinions of experts. Any documents created in contemplation of the current proceedings would of course attract litigation privilege. However, this class was considered to be wider and was ordered by Mr Justice Kelly on the basis that the defendants had already acceded to the plaintiffs’ request for all documents in the possession, power or procurement of the defendants concerning any evaluation of whether the features, configuration or design of the defendants’ product was the subject of patent protection.

Documents relating to an evaluation by the patentee of the patentability of the invention at issue in proceedings was also ordered by Miss Justice Finlay Geoghegan in the Schneider Case and in the subsequent case of Medinol Ltd v Abbott Ireland and Others and so it seems the discoverability of such documentation has become par for the course. Such documents can include an evaluation by the plaintiff or its agents of the benefits over and above the state of the art of the claims of a patent. In addition, documentation relating to any experimental use of the invention contained in the patent(s) by the plaintiff will also be discoverable.

In Ireland, there is also no exemption for discovery of documents relating to “commercial success” as contained in the Civil Procedure Rules. When commercial success is an issue, i.e. to the issue of obviousness, then documentation regarding exploitation of the patents, particularly through licensing arrangements, may be subject to a discovery order. In the Medtronic Case, Mr Justice Kelly followed the approach in the English case of Re: John Guest (Southern) Limited Patent and ordered discovery of such documents on the basis that the defendants contended that commercial success will be relied upon in support of their claim of obviousness. However, the judge was not prepared to order discovery of a separate and broader category of all documentation relating to the value of the patents and/or the calculation of royalty rates and other payments for the patents as copies of any licence agreements would be discovered and deemed sufficient.

Discovery in infringement proceedings

For patent infringement proceedings, there is no procedure under the Rules of the Superior Courts (as amended) that mirrors the Civil Procedure Rules in allowing a defendant to avoid standard disclosure of documents relating to the infringement issue by serving on a plaintiff full particulars of the product or process alleged to infringe including drawings and illustrations. Having said that, a defendant in Irish patent proceedings could adopt such an ad hoc tactic and this may have the effect of demonstrating to the judge in cases of dispute that such documents are not necessary for the fair disposal of the proceedings and/or to save costs.

The most effective way for a defendant to try and achieve this is to set out detailed particulars of the product as part of the pleadings in the case and/or in correspondence during the voluntary discovery stage by counter-offering to voluntarily discover a much more limited and focused class of documents so as to enable the issue of infringement to be resolved but yet minimise the burden of disclosure for the defendant. Such a description would most likely have to satisfy the English test of being sufficient to enable all issues of infringement to be resolved.

For infringement matters, the focus is on the defendant’s product or process and whether there has been an infringement of the patent claims. For this reason, any documents concerning an evaluation by the defendant on whether its product(s) infringe patents will be discoverable in infringement proceedings. In the Medinol Case, any communications between the defendant and its distributor concerning possible patent infringement were discoverable under the Peruvian Guano principles, as such documents, if existing, would damage the defendant’s denial that the accused products do not infringe the plaintiff’s patents.

The reciprocity concept is also applicable in the infringement context in that if a plaintiff to an infringement action has sought discovery of documents relating to a defendant’s consideration of potential patent infringement, then a court is likely to order that the plaintiff also discover any documents in its power, possession or procurement concerning the plaintiff’s consideration of patent infringement by third parties including the defendant. Such discovery was ordered on this basis in the Medtronic and Medinol Cases.

Depending on the nature of the claimed infringement and the content of the Particulars of Infringement, it is more likely that documents relating to the design and manufacture of the defendant’s product will be relevant and necessary for discovery purposes rather than documentation relating to the inception, creation and development of the product. After all, the issue of infringement will be one of fact and based on the finished product. Therefore, insight into the design and manufacturing process can assist in demonstrating whether a product comes within the terms of a patent claim. This approach was adopted by Miss Justice Finlay Geoghegan in the Schneider Case. Discovery of documents relating to the design of alleged infringing products was also ordered by the same judge in the Medinol Case.

The defendant in an infringement action may also seek extensive discovery of documentation concerning a patented product’s development, approval process, labelling and marketing in order to analyse the patented product so as to understand the patent claims covering the product and in order to compare its product with the patented product for the purposes of evaluating potential infringement of the patent claims. In the recent Medinol Case, Ms Justice Finlay Geoghegan held that the crux of the issue in patent infringement proceedings is a comparison of the defendant’s alleged infringing product and the patent claims. To this extent, a broad request for discovery of documents relating to the plaintiff’s patented product would not be permissible and either would a request for physical samples of the patented product in circumstances where the product was commercially sold.

Miss Justice Finlay Geoghegan held that in view of the objective and purposive construction of patent claims by the Court, a much more limited class of documents should be discovered in order to assist the defendant in understanding the plaintiff’s patented product so that expert evidence could be obtained, if necessary. Accordingly, discovery of the following category of document was ordered by the judge:

“All documents which show the design, structure, function, description and operation of each plaintiff covered product, including, but not limited to, product specifications and drawings (e.g. engineering drawings), protocol and manuals.”

Finally, documents relating to a potential ownership dispute concerning the patent will not be considered by the Court to be relevant and necessary to the issue of infringement if the proceedings are taken by the registered proprietor of the patent. In other words, Irish courts will not order discovery to enable a defendant to look behind the statutory register and try and mount a challenge regarding entitlement to sue.


The rules regarding discovery in Ireland are not as detailed as those contained in the Civil Procedure Rules. Instead of specific exemptions for certain categories of documents being discovered in patent proceedings, Irish Courts will still be required to determine on a case by case basis whether any particular category of documentation must be discovered in cases of dispute. However, the above-mentioned cases already provide a useful benchmark for litigants to determine what will or won’t constitute a permissible discovery request in Irish patent proceedings.