Client-attorney privilege in patent matters: Scope, limitations and best practices

Understanding the concept of privilege is vital for navigating the discovery process during international patent disputes. Valérie Stephann provides expert guidance on the key points to consider. 

International patent disputes are on the rise. In this context, European companies are increasingly likely to be involved in foreign proceedings, particularly in common law countries such as the United States. These proceedings generally involve discovery mechanisms, which can compel a party to produce internal and confidential documents to the opposing party. 

Discovery is a phase of common law proceedings during which each party is required to disclose to the other all documents relevant to the dispute, including those that are unfavourable to them. Only documents validly protected by a recognised privilege can be excluded. 

In this context, the issue of privilege becomes crucial. In this regard, the concepts of confidentiality, professional secrecy and privilege should not be confused. 

The episode "Keeping it confidential: Client-attorney privilege" from the podcast INSIGHT epi (the podcast for European patent professionals) specifically highlights the limits and conditions for recognising the privilege attached to communications between clients and patent attorneys. This article draws on that episode.  

Confidentiality, professional secrecy and privilege: Beware of confusion 

The concepts of confidentiality, professional secrecy and privilege are frequently confused. However, they do not offer the same level of protection, particularly in the event of a dispute. 

• Confidentiality is based on contractual or organisational commitments. It allows for limiting the dissemination of information but does not prevent a judge from ordering its production in legal proceedings.
• Professional secrecy is a legal or ethical obligation incumbent upon certain professionals, such as lawyers or patent attorneys. It governs their conduct but does not necessarily guarantee that the documents in question will be protected against disclosure in court, especially outside the jurisdiction in which they are qualified to work.
• Privilege (often referred to as legal professional privilege or attorney-client privilege) is a procedural rule. It allows for the refusal to produce certain non-public internal documents in the context of litigation, particularly during discovery proceedings. 

The existence and scope of the relevant privilege depend, in particular, on: 

• The identity of the advisor,
• The capacity in which they act,
• The legal system that assesses the privilege claim. 

The privilege is determined by the courts, not by the parties themselves. 

Rule 153 EPC: European patent attorney privilege before the EPO 

Rule 153 of the European Patent Convention (EPC) constitutes the legal basis for the privilege applicable to attorneys registered with the European Patent Office (EPO). 

The privilege applies when: 

• The adviser is acting in their capacity as an attorney;
• The disclosure is related to the performance of this function; and
• The client has not expressly waived the privilege. 

The following are specifically covered: 

• assessments relating to patentability;
• the preparation and conduct of proceedings before the EPO;
• opinions on the validity, scope, or infringement of a European patent. 

However, this protection is strictly limited to proceedings before the EPO. 

Communications relating to activities outside the scope of the attorney's duties (for example, tax, commercial, licensing or management advice) are not covered. European patent attorneys working in-house within a company must be particularly vigilant when they hold multiple positions. 

The importance of national law and its recognition abroad 

The limited scope of Rule 153 EPC makes national laws decisive, particularly in the event of international disputes. Some states, such as Switzerland, have introduced explicit rules allowing patent attorneys to refuse to produce documents in court. 

US courts generally examine whether an equivalent privilege exists in the foreign counsel's home country. If such protection exists, it may be recognised. If not – particularly when the applicable national law did not provide equivalent protection at the time the documents were created – the privilege may be denied. 

Practical recommendations for preserving privilege 

The INSIGHT epi episode concludes with several concrete recommendations: 

• Ensure that documents are prepared under the supervision of qualified counsel (EP representative or qualified national counsel); documents prepared by administrative staff, interns, or unqualified employees must be subject to sufficient and documented supervision.
• Strictly separate legal patent advice from business advice, and avoid mixing them in the same document. For example, an in-house EP representative in a management position must clearly distinguish between infringement or validity analyses and commercial considerations related to risk or strategy. Otherwise, legal information risks being "contaminated" by commercial elements, resulting in the loss of privilege for the entire document.
• Use the "confidential and privileged" designations judiciously, and on the relevant documents only. Misuse of these designations can undermine the credibility of the privilege claim.
• Raise awareness among internal teams about the risks associated with written communications.
• Do not rely blindly on privilege, the scope of which remains uncertain, even in the US. 

Key takeaways for patent attorneys 

Patent privilege is not presumed: it is built. In the context of international litigation and discovery, only rigorous management of communications – both in terms of substance and form – can preserve its effectiveness and prevent the disclosure of sensitive documents during litigation. 

Here are five key points to keep in mind: 

For further guidance on preserving privilege, please speak to your Novagraaf attorney or contact our team.