What is a European patent and how is it a bundle of national patents?
A European patent is granted by the European Patent Office (EPO) through a single centralized examination and grant procedure. Despite the unified process, the outcome is not a single supranational right. Instead, a European patent becomes a bundle of national patents, one component in each country where the applicant has sought protection and completed the required post-grant steps. That distinction shapes everything from how the patent is maintained to how it is enforced and attacked.
The European Patent Convention and the EPO
The European Patent Convention (EPC), signed in Munich in 1973 and revised in 2000, established the legal framework under which the EPO grants patents through a centralized procedure independent of national patent offices. The EPC provides a single grant procedure conducted in one of three official languages (English, French, or German), covering patent protection across EPC Contracting States.
Applicants file one application, correspond with one office, and receive one grant decision. That procedural unity is the EPC's core efficiency gain over filing separate applications in each country.
What the bundle means: EPC Article 64
The "bundle" character of a European patent is established by EPC Article 64. Under Article 64(1), a European patent shall confer on its proprietor, in each Contracting State in respect of which it is granted, the same rights as would be conferred by a national patent granted in that State. The EPC does not create a unitary pan-European right. It creates separate national rights that originate from one examination and grant procedure.
Under Article 64(3), any infringement of a European patent shall be dealt with by national law. Once the EPO grants and the patent is validated, the EPO has no role in infringement disputes. National courts apply their own substantive law.
Once granted by the EPO, a European patent becomes a bundle of patents having equivalent effect to national patents, which must be validated in each of the selected Contracting States. The practical result is that a European patent with validation in ten states creates ten separate legal instruments. Each national component has its own renewal fee schedule, can be separately licensed or assigned, and can be separately attacked for invalidity in that country's courts.
Post-grant validation: activating the bundle
EPO grant does not automatically activate the patent in any EPC Contracting State. After EPO grant, a European patent must be validated in each designated Contracting State for it to take effect there. Validation is completed state by state, and the translation requirements that often accompany it are detailed below. Missing the validation period in a given state means the patent has no effect there, regardless of the EPO grant.
The London Agreement and translation costs
Before the London Agreement, holders had to translate the entire patent specification into the official language of every validation country, a significant post-grant expense.
The London Agreement (the Agreement on the Application of Article 65 EPC) entered into force on 1 May 2008 and reduces post-grant translation costs for patent holders validating in signatory EPC states. The reduction depends on the country's category:
| Category | Translation requirement |
|---|---|
| Official language is English, French, or German | No specification translation needed for validation |
| London Agreement state with another official language | Claims translation into national language only |
| Non-signatory state | Full specification translation required |
Under the London Agreement, EPC member states whose official language is English, French, or German require no translation of the patent specification for validation. EPC states with another official language that have ratified the agreement generally require only a translation of the claims into their national language, not a full specification translation. EPC states that did not ratify the London Agreement still require a full translation of the patent specification into their national language as a condition of validation.
Validation costs therefore vary substantially across the EPC territory. The decision about which states to validate in should weigh translation expense alongside the commercial importance of each market.
Central opposition versus national invalidity actions
The EPO provides one mechanism for attacking a granted European patent centrally. Any person may file an opposition to a granted European patent at the EPO within a set window following publication of the mention of grant in the European Patent Bulletin, challenging the patent centrally rather than in each national court. A successful EPO opposition has the effect of centrally invalidating or limiting the patent in all states in which that patent has effect. This makes EPO opposition the most efficient vehicle for clearing a blocking European patent across multiple markets at once.
Once the EPO opposition window closes, validity can only be attacked through national proceedings. Validity of a European patent may be challenged separately in national courts of each jurisdiction where it has effect, and different courts may reach different conclusions on validity. The bundle structure means the same patent can be found valid in one jurisdiction and invalid in another, producing fragmented outcomes for both parties.
Enforcement: national courts, national law
Infringement of a European patent is enforced through national courts applying national law, with courts in each country determining what constitutes infringement and what remedies are available. Because each national component is litigated under national rules, litigation cost, speed, available remedies, and forum culture differ significantly across EPC states. For multi-jurisdictional enforcement, the bundle structure requires decisions about where to sue, whether to coordinate parallel proceedings, and which forum's outcome matters most for commercial purposes.
The Unitary Patent: an alternative to the bundle
A newer option allows applicants to avoid managing individual national components after EPO grant. The Unitary Patent system became operational on June 1, 2023, offering an alternative to the bundle approach by providing uniform protection across participating EU member states through a single registration, with disputes handled by the Unified Patent Court. A patent owner who requests unitary effect following EPO grant receives a single instrument instead of a bundle, with one renewal fee and centralized jurisdiction for both infringement and revocation.
The Unitary Patent covers only participating EU member states and does not automatically cover the full EPC territory. EPC Contracting States that are not EU members fall outside the Unitary Patent system, as do any EU states that have not yet ratified the Unified Patent Court Agreement. A combined strategy (requesting unitary effect for participating states, plus individual national validation in additional EPC states) is often the right approach for portfolios with broad geographic targets.
Practical notes for practitioners
- Grant is not protection. The EPO grant decision is the starting point for national rights, not the endpoint. Validation must be completed in each target state, and missing a validation deadline extinguishes rights in that state permanently.
- Track validation requirements by country. Translation obligations and fees vary by whether the target state signed the London Agreement, what official language it has, and what its national validation fee structure is.
- Use EPO opposition strategically. The centralized opposition is the most cost-effective way to attack a European patent across multiple markets simultaneously. After the opposition window closes, only separate national actions remain.
- Account for the bundle in infringement enforcement. Each national component must be enforced in its own court under its own law. Decide which jurisdictions matter commercially and plan parallel actions accordingly.
- Consider the Unitary Patent for EU-focused portfolios. Where the commercially important markets are primarily in Unitary Patent participating states, the Unitary Patent simplifies renewals and consolidates enforcement and revocation in a single court.
- Coordinate closely on claim scope. Because the bundle creates national patents from a single granted claim set, the claims as granted govern every national component. Narrow amendments during prosecution or opposition affect all jurisdictions simultaneously.