The European Patent Opposition Procedure offers an effective dispute resolution mechanism for European patent holders and interested parties (such as competitors), fostering an environment of fair competition. This article aims to provide a comprehensive overview of the European Patent Opposition Procedure, detailing its characteristics and operational mechanisms.

PART 1: Overview of the Opposition Procedure

The opposition procedure of the European Patent Office (EPO) is an administrative process that allows any party to oppose a European patent within nine months of its grant. Compared to invalidity proceedings conducted in individual member states of the European Patent Convention (EPC), the EPO opposition procedure provides an opportunity for centralized revocation of a European patent.

This procedure is advantageous as it allows for the efficient challenge of a patent’s validity on a broad scale, covering all EPC member states in which the patent is effective. It ensures that the legal standards of patentability are consistently applied, thereby maintaining the quality and integrity of granted patents across Europe.

PART 2: Time Limits and Eligibility for Filing an Opposition

The time limit for filing an opposition is nine months from the date of grant of the European patent, and this period is non-extendable. The opponent must submit a notice of opposition within this time frame, providing the grounds and supporting evidence for the opposition.

Apart from the patentee of the concerned European patent, any natural or legal person may file an opposition, regardless of whether they have a direct interest in the patent. In practice, competitors often use a “straw man” to file an opposition to conceal their identity and avoid potential conflicts.

PART 3: Opposition Fees

The opponent is required to pay an opposition fee to initiate the European Patent Opposition Procedure. According to the EPO’s regulations, the opposition fee is €880 (as of 2024). This fee does not cover additional costs that may arise, such as attorney fees.

PART 4: The Opposition Division

The “Opposition Division” of the European Patent Office (EPO) is responsible for handling opposition cases. An opposition division typically consists of three technically qualified examiners, with at least two of them not having been involved in the previous grant proceedings. The division’s task is to examine the filed opposition, collect and evaluate the relevant arguments and evidence, and ultimately make a decision.

During the opposition process, the opposition division may hold oral hearings upon request, facilitating communication between the parties involved and ensuring that the procedure is conducted fairly and effectively. These hearings allow for the presentation of arguments and evidence in a structured manner, contributing to a thorough examination of the case.

PART 5: Grounds for Opposition

The grounds for opposition to a European patent, as specified under Article 100 of the European Patent Convention (EPC), include the following three categories:

• Lack of Patentability (Articles 52-57 EPC): The subject matter of the European patent does not meet the patentability requirements. Common specific grounds under this category include:
  • Lack of novelty
  • Lack of inventive step
  • The subject matter is not patentable (e.g., certain types of subject matter are excluded from patentability under the EPC)
• Insufficient Disclosure: The European patent does not disclose the invention in a sufficiently clear and complete manner, such that a person skilled in the art is unable to carry out the invention.
• Extended Subject Matter: The subject matter of the European patent extends beyond the content of the application as originally filed.

It is important to note that issues of clarity and unity of invention are not considered valid grounds for opposition in the context of the European Patent Opposition Procedure.

PART 6: Opposition Procedure Flow

The opposition procedure for a European patent typically includes the following steps:

• Filing the Notice of Opposition: The opponent must submit a notice of opposition within nine months of the patent grant, detailing the scope, grounds, and supporting evidence for the opposition.
• Preliminary Examination: The European Patent Office (EPO) will conduct a preliminary examination of the notice of opposition to ensure it meets the formal requirements.
• Invitation to Respond: If the opposition is admissible, the EPO will invite the patent proprietor to respond within four months. During this period, further examination is conducted. The patent proprietor may submit arguments and evidence against the opposition, as well as amended claims. The proprietor can submit multiple sets of claims for the Opposition Division to consider, often including a broader set as the “main request” and narrower sets as “auxiliary requests”. This strategy allows for fallback options in case the main request is not accepted.
• (Typically) Oral Proceedings: Both parties are usually invited to participate in oral proceedings. These hearings are often conducted via video conference, allowing for direct communication and a thorough examination of the case.
• Issuing the Decision: The EPO will make a final decision based on the arguments and evidence presented by both parties. There are three possible outcomes:
  • The European patent is upheld as granted.
  • The European patent is maintained in an amended form.
  • The European patent is revoked.

This structured procedure ensures a thorough and fair examination of the opposition, maintaining the integrity and quality of European patents.

PART 7: Oral Proceedings

Both the opponent and the patent proprietor may request oral proceedings under Article 116(1) EPC, and typically do so. Here, we detail the regulations and process concerning these oral proceedings.

• (a) Scheduling: There is usually a minimum of six months between the issuance of the summons to oral proceedings and the actual hearing date.
• (b) Preliminary Opinion: The summons generally includes the Opposition Division’s preliminary opinion on the case.
• (c) Final Written Submissions: Both parties may submit final written statements in response to the preliminary opinion up to two months before the oral proceedings. In particular, the patent proprietor may submit one or more amended sets of claims.

Approximately one to two weeks before the oral proceedings, the three members of the Opposition Division typically meet to discuss all the written submissions. Thus, at the start of the oral proceedings, the Division’s view may differ from the preliminary opinion attached to the summons.

During the oral proceedings, both the opponent and the patent proprietor present their arguments. At the end of the hearing, the Opposition Division announces its decision (often without detailed reasoning, or with only very brief reasoning). The detailed written decision is typically issued within six months. The possible outcomes of the opposition decision are to maintain the European patent as granted, to maintain it in an amended form, or to revoke it.

The timeline for the opposition procedure can be referenced in the following diagram.

After the Opposition Division issues its written decision, any party adversely affected may initiate an appeal procedure. Firstly, within two months from the date of the written decision, a notice of appeal must be filed, accompanied by payment of the appeal fee. Secondly, within four months from the date of the written decision, a statement of grounds for appeal must be submitted. Further details regarding the appeal process will not be elaborated here.

PART 8: Advantages of the Opposition Procedure

Compared to invalidity proceedings initiated in individual member states of the European Patent Convention (EPC), the opposition procedure conducted by the European Patent Office (EPO) offers three main advantages for opponents.

Firstly, the outcome of the opposition applies to all countries covered by the European patent, thus avoiding the need to initiate multiple invalidity proceedings in different countries.

Secondly, in recent years, the EPO has made efforts to shorten the overall duration of the opposition procedure. Statistics indicate that the average processing time for cases is approximately 19 months.

Lastly, compared to national court proceedings, the costs associated with the opposition procedure at the European Patent Office are generally lower.

Conclusion

According to recent statistics from the European Patent Office, approximately one-third of oppositions result in the revocation of the European patent in question, while 35%-40% lead to the maintenance of the patent in amended form. Therefore, the opposition procedure provides an effective and cost-efficient means for the public to limit or revoke granted European patents.

By gaining a deeper understanding of the specific operational processes and characteristics of the opposition procedure, stakeholders can better formulate intellectual property strategies, effectively protect their interests, and plan against competitors.