European Patents - The Basics

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What is a patent

A patent is a legal right to protect new inventions. It allows the owner of the patent (the patentee) to take legal action against others who use the invention without their permission in a particular jurisdiction. A patent has a maximum life-time of 20 years in most countries. What a patent does not do is give the owner an automatic right to use the invention. The  owner still needs to take care to avoid infringing other people’s rights.
Historically, to obtain a patent in a country you had to apply to the patent office in that country. If patent protection across Europe was wanted, separate applications were needed for each country. Since 1978, however, it has been possible to file a European patent application to obtain a European patent which may take effect in a number of countries. 

What is a European patent?

Rather than applying for each national patent individually, individuals and companies can apply  to the European Patent Office (EPO) for a European patent. The EPO will handle the examination of this European patent application, rather than every individual country performing their own assessment. This makes it easier and cheaper for patent applicants to obtain patent rights in Europe.

Once the EPO considers a European patent application is acceptable, the patent is granted. The European patent is then converted into national rights in each country through a process called “validation”. The national rights can be obtained in countries that are members of the European Patent Convention (EPC). This includes the UK, France, and Germany, and a full list of the countries is presented at the bottom of this article. Please note that the members of the EPC are not all members of the European Union (EU), although all current members of the EU are members of the EPC.

You can choose to apply for protection in any or all of the member countries of the EPC. Generally, if you want patent protection in three or more of the member countries, a European patent is cheaper to obtain than individual national patents.

Since 2023, a new European Unitary Patent has become available which protects most countries in the EU with a single patent, rather than a “bundle” of national rights, as with the standard European patent. It is expected that this will significantly reduce the cost of obtaining patent protection across most of the EU. We have discussed the Unitary Patent in more detail in this article.

Who can apply for a European patent?

A company or an individual can apply for a European patent. They will have to confirm that they own the invention to be granted a patent.

An application for a European patent can be made directly by you, or you can authorise a European Patent Attorney to make the application on your behalf. European Patent Attorneys are professionally qualified people who are experienced in dealing with the EPO and the application procedure.

If you do not have either a residence or a principal place of business in one of the member countries of the EPC, you must be represented by a European Patent Attorney throughout the application procedure, except for the initial filing of the application.

The process of obtaining a European patent


Generally speaking, you should file a patent application for your invention once you have a working prototype or proof-of-concept for your invention. This allows you to confirm that your invention works and also that the core function of your invention is less likely to dramatically change in the near future as you develop it further.

More complex inventions, particularly those in the life sciences or chemical fields, may require additional work before a patent application should be filed.

Once you are at this stage, you will work with your patent attorney to write a patent specification (drafting), setting out what your invention is (the description), and what you want to protect (the claims). This typically takes around a month but can be prepared much more quickly in emergency situations. Once this document has been prepared, it can be filed with a patent office, such as the EPO. 


Usually, when a European patent application is made, it will claim priority from an earlier patent application for the same invention, for example an earlier UK patent application. In order to claim priority, the European patent application must be filed no later than 12 months after the earlier application with certain limited exceptions. The claim to priority must be made within 16 months of the filing of the earlier application.

Claiming priority means that for some purposes your European patent application is back-dated to the date of the earlier patent application. In particular, the patentability of your invention is judged against the public knowledge at the date on which the earlier application was filed, insofar as the earlier application contains sufficient information about the invention. This date is known as the priority date of the European patent application. For example, you may wish to file initially a relatively cheap UK patent application at an early stage in the development of your invention, in order to establish a priority date. Following this first filing, you have a year to develop your invention further, and to work out whether it is commercially viable, before you have to decide whether to invest in a European patent.

It is possible to file an application for a European patent without claiming any priority. It is also possible to make a European patent application via an international application under the Patent Cooperation Treaty (PCT) PCT applications are discussed in detail in this article. We can provide you with further information about these options if you wish. In the remainder of this information sheet it is assumed that you are filing a European patent application claiming priority from an earlier patent application filed 12 months previously.


A few months after the application is filed, an examiner at the EPO will perform a search for inventions and public disclosures which are similar to your invention. They will then send you a search report which lists documents that have content similar to your invention.

In order for a patent to be granted, the invention must be new compared to what is already publicly known. Patent attorneys refer to this requirement as “novelty”. The invention must also not be obvious. We say the invention must have an “inventive step”.

As part of the search report, the examiner will include an opinion on whether the invention (as defined by your claims) can be patented based on this criteria and other rules. 
For about a year, nothing will immediately happen. However, you will have the opportunity in this time to file other patent applications in other countries based on the initial EPO application. This “priority” process is discussed later.

Approximately 18 months after the priority date, the EPO will publish your patent application and their search report on their website. At this point, your patent application and the information in the specification is publicly available.

Within 6 months of this publication, you must request that the application be examined if you want it to proceed to grant. As part of this process, official fees must be paid.

If the examiner has given reasons why they think the patent should not be granted, then you must present reasoned arguments to the EPO to counter their objections. You can also change the claims to address the examiner’s objections. A patent attorney can help you with this process.


Typically after a few months (but it may take significantly longer), the examiner will review your response. If they agree that the patent can be granted, then the application will proceed to the grant stage. If not, the examiner will prepare and send you an examination report, which lists the reasons why the patent can still not yet be granted. You can respond to these objections with a further written response. You typically have 4 to 6 months to file this response.

This process can repeat multiple times, as you argue backwards and forwards with the examiner, and make changes to the application.

For a typical European patent application, the entire process from filing the application to it being granted will usually take about three to four years. During this time, it is also necessary to pay yearly “renewal” fees to the EPO to keep your application pending.

The examiner may eventually decide that your patent application cannot be granted. If this occurs, the examiner will refuse your application. Before this happens, you will have the opportunity to have a hearing with the examiner to discuss the issues. If this is unsuccessful, it is possible to file an appeal.

Grant process

The grant procedure is discussed in detail here. A brief summary is given below.

After the examiner has decided that the application can be granted, the EPO will send you an Intention to Grant communication. This communication contains a copy of the text of the patent application for your final approval.

Once you are happy with the text of the patent, you must pay official fees to the EPO and you must also file translations of the claims into French and German (assuming your patent application was filed in English). The patent will then be granted.

Within 3 months of grant, you must apply in each of the countries you want the European patent to have effect. This process is called “validation”. Some countries require that you translate the claims or even the whole patent into their local language. Generally the more countries you validate in, the higher the cost of this will be.

Alternatively, from 1 June 2023, it will be possible to request that the EPO issue a “unitary” patent. A unitary patent is a single indivisible right (similar to that available for trade marks and registered designs) that has effect in some EU countries. Generally it is expected that the unitary patent will reduce the costs for obtaining patent protection in Europe, and also in reducing litigation costs.

However, it should be noted that non-EU countries (such as the UK) and some EU countries (e.g. Spain and Poland) are not part of the unitary patent package, and so granted European patents will need to be validated in these countries the conventional way.

Read more about unitary patents here

After grant

Once a conventional European patent has been granted, it effectively splits into a group of separate national patent rights. You can choose to let your patent rights lapse in one or more of the chosen countries, without affecting the patent rights remaining in other countries. You also stop paying yearly renewal fees to the EPO and instead pay them individual fees to each of the patent offices of the countries that you validated the patent in.

For a unitary patent, you will continue to pay a yearly renewal fee to the EPO. It is not possible to let your rights lapse in any individual country that is part of the unitary patent.
Up to 9 months after your patent is granted, anyone can file an opposition to try to get your patent revoked. Oppositions are discussed more here.

How do I enforce my patent?

How do I enforce my patent?

Once your patent has been granted and validated, it is enforceable in the chosen countries. This means that anyone using your invention without your consent in those countries will be infringing the patent.

Acting though a local attorney, you can tell anyone using your invention to stop, and eventually bring legal action against them to force them to stop and potentially to collect compensation (e.g. legal “damages”) from them for their infringement. You cannot sue for infringement until the European patent application has been granted. However, once your application has been granted, it may be possible to claim damages back to the date on which your application was published.

For conventional European patents, you will need to bring separate legal action in each country where you wish to enforce your rights. However, this is changing with the introduction of the Unified Patent Court (UPC).

The UPC will begin hearing cases on 1 June 2023. For a transitional period of 7 years (which may be extended) it will be possible to bring legal action in relation to conventional European patents before either the national court or the UPC.

Until the transitional period ends, it is possible to “opt-out” a European patent from the UPC so that it is only possible to bring legal action based on the European patent in national courts.

After this period ends, the UPC will take exclusive jurisdiction on EP patents in relation to countries that have signed up for the UPC.

For the countries which are not participating in the UPC (e.g. UK, Spain, Poland), you will need to bring separate legal action in each country as with conventional European patents. 
Only the UPC will be able to hear cases relating to unitary patents.

If you are considering litigation, you should discuss this with your patent attorney or with a solicitor/lawyer.  

What can we do for you?

A European Patent Attorney can handle all aspects of obtaining a European Patent, including writing the application.

Employing a European Patent Attorney may increase your costs in the short term, but it is likely to give you a more secure European Patent.  European Patent Attorneys are bound by professional rules of conduct which prevent us from telling anyone about your invention without your consent.

We can advise you on other aspects of intellectual property such as Trade Marks, Copyright, Designs, licensing and litigation, in Britain, Europe and around the world.

The members of the EPC as at 1st October 2022


Any or all of the above countries can be designated in a European Patent application.

It is also possible to “extend” the protection of a European patent into the following countries. The details of this are discussed in this article.

Bosnia & Herzegovina

Moldova is expected to become an EPC member in the near future.


1 Liechtenstein and Switzerland together count as a single designation
2 These “extension” and “validation” countries cannot be designated as such in a European Patent application, but the national law in each country provides for “extension” or “validation” into that country of the rights conferred by a granted European patent. We can provide further information about this if you are interested in any of these countries.

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This information is simplified and must not be taken as a definitive statement of the law or practice.