Patent Infringement
What Does It Mean to Infringe a Patent?
Patents protect inventions. Patent owners have the legal right to stop others from using their inventions. If someone uses a patented invention without the patent owner’s permission, then they would potentially infringe the patent.
Who can I turn to for advice about patent infringement?
The Chartered Patent Attorneys at ip21 can advise you on matters relating to patent infringement.
· Speak to us if you’re unsure whether something you’re doing (or planning to do) might infringe a patent.
· Likewise, get in touch if someone else appears to be doing (or planning to do) something that might infringe a patent that you own.
What kinds of activities can infringe a UK patent?
In the UK, the infringement of a UK patent is defined by Section 60 of the UK Patents Act. You can read the legal definition here.
- If the UK patent covers a product, infringement might happen by:
· Making the product.
· Disposing of it (this includes selling it).
· Offering to dispose of it (this includes offering to sell it).
· Using it.
· Importing it.
· Keeping it (whether or not they plan to dispose of it).
- If the UK patent covers a process (a way of doing something), infringement might happen by:
· Using the process in the UK.
· Offering the process for use in the UK.
However, this only counts as infringement if the person knows (or it is obvious) that using the processes without permission would infringe the UK patent.
- If someone makes a product by directly using a process that is protected by a UK patent, infringement might happen by:
· Disposing of the product (e.g., selling it).
· Offering to dispose of it (e.g., offering to sell it).
· Using it.
· Importing it.
· Keeping it (whether or not they plan to dispose of it).
- There is also contributory infringement, meaning that a UK patent might be infringed by:
· Supplying someone in the UK with the means for putting the invention into effect in the UK.
· However, this doesn’t apply to activities relating to staple commercial products, unless the supplier has the purpose of inducing someone else to infringe the UK patent.
· Contributory infringement is also known as indirect infringement, because it relates to indirectly causing someone else to directly infringe the patent.
What does a UK patent actually protect?
A patent includes a section called the “claims”, which define what is protected. The rest of the patent is helpful for explaining the meaning of the claims.
Even if the activity isn’t within the literal meaning of the claims, it could still infringe the patent if the act is equivalent to what is protected by the patent.
A UK patent will only restricts acts that take place in the United Kingdom, including UK territorial waters and the Isle of Man.
What defences are available if you’re accused of infringing a UK patent?
You might have a defence if:
· The patent isn’t in force.
· Your actions fall outside the scope of the claims.
· The patent isn’t valid to begin with.
You could seek to revoke a UK patent if it should never have been granted.
When do patent rights become enforceable in the UK?
A UK patent can only be enforced after it has been granted by either:
· The UK Intellectual Property Office (UKIPO), or
· The European Patent Office (EPO) in cases where the UK is designated.
Publication of a patent application provides provisional rights
The owner of a UK patent application or a European patent application gains some provisional rights when it is published. However, these provisional rights are only enforceable in the UK after the grant of a patent. If enforcing provisional rights, the claims of the patent application as published will be compared to the claims of the patent as granted.
For how long will patent rights be enforceable in the UK?
A UK patent lasts up to 20 years from its filing date, as long as annual renewal fees are paid on time. For certain inventions, such as for pharmaceuticals or plant protection products, the term can be extended by a Supplementary Protection Certificate.
How can someone use a patented invention legally?
Consent to use a patented invention can be given with the awarding of a licence for a fee. However, in some situations a licence may not be needed because third party rights might apply that allow activities that would otherwise be restricted by a UK patent.
These include:
· Prior user rights: If a third party was already using (or preparing to use) the invention in good faith before the priority date of the UK patent, then they may be allowed to keep doing it.
· Patent restoration: If a UK patent lapses and is later restored, people who started using the invention in good faith before publication of the restoration request might be allowed to continue.
· Certain uses are exempt: For example, acts that are private & non-commercial may be exempt from infringement. Acts that are done for experimental purposes may also be allowed.
· Exhaustion of rights: Once a product is put on the market in the UK or the European Economic Area, by the patent owner, they can’t use their UK patent to stop others from reselling it or using it in the UK. Since Brexit, the UK Government has maintained this UK+ approach. However, this position was not reciprocated by the European Union, meaning that if a product is placed on the market in the UK, then it will be unlikely that this will exhaust IP rights that cover member states of the EU.
Third party rights tend to be quite narrowly defined. It is recommended to seek advice from a Patent Attorney before relying upon them.
Are you concerned about infringing someone else’s UK patent?
Here are some tips if you provide (or are planning to provide) a product or service in the UK:
· Freedom-to-operate searching: This checks whether there are any patents that you might infringe. This can reduce the risk of being sued later for patent infringement. Also, if you can demonstrate that you have done due diligence, this may lower the amount of any damages if you’re found to have infringed inadvertently.
· Seek your own patent protection: If infringement proceedings are brought, then there may be an opportunity for you to cross-licence your technology with the other patent owner. A patent application should be filed before you launch your product or service.
· Trade in the name of a limited company: This avoids the risk of you having personal liability.
· Take out patent infringement insurance: A way to mitigate risk would be to put in place an insurance policy that protects your business from having to pay out damages, as well as legal costs.
· Prepare arguments: If you discover a patent that you’re concerned about, consider how you will respond, just in case infringement proceedings are ever brought against you.
What can you do if you are accused of infringing a UK patent?
If you are accused of patent infringement, here are some ways that the problem could be resolved:
· Show that the patent isn’t enforceable.
· Prove that your activities don’t fall within the patent’s scope.
· Demonstrate that the patent isn’t valid.
· If the above fails, negotiate a licence agreement with the patent owner.
· If the owner will not give you a licence, then you must stop the infringing activity.
If the patent is invalid, it’s worth considering opportunities to seek revocation before the UKIPO or the EPO. Alternatively, you could offer to take a royalty-free licence, in exchange for you not bringing revocation proceedings.
What can you do if someone is infringing your UK patent?
If you own a UK patent and someone is using your patented invention without permission, seek advice on whether you can:
· Get an injunction to stop them.
· Claim damages or a share of their profits.
· Ask for destruction or delivery up of infringing products.
· Obtain a declaration confirming that the patent is valid and infringed.
· Recover some of your legal costs.
· Alternatively, you could consider offering them a licence on reasonable terms.
What should be done before bringing infringement proceedings?
It’s important to seek advice from a Patent Attorney to make sure that:
· Your UK patent is still in force.
· The other person’s actions really do fall within the scope of your patent.
· You identify whether any fall-back positions are available, in case the other party successfully challenges the validity of your patent.
· You avoid threatening to bring infringement proceedings, because you could face a counter-claim if a threat is seen as being groundless.
How can an IP dispute be resolved?
This guidance mainly relates to infringement of a UK patent. It’s worthwhile considering whether any other intellectual property rights might be infringed, such as patents in any other countries.
In many cases, an amicable way forward may be available, if a licence agreement can be agreed. Disputes can be resolved at low cost if the parties can compromise during negotiation or mediation.
You may find it helpful to decide what to do by asking for an opinion to be prepared by a Chartered Patent Attorney, or the UK Intellectual Property Office (UKIPO).
If court action is needed, the High Court deals with high-value disputes. Smaller cases can be handled by the Intellectual Property Enterprise Court (IPEC), which is a specialist court that can provide a faster and affordable way to access justice.
Need Support?
We recommend that you seek advice on the available options for resolving any IP disputes. Your approach will depend upon the commercial context, as well as your appetite for risk. Our Patent Attorneys at ip21 are here to support you, however you decide to proceed.
Written by Mark Saunders, Senior Patent Associate
September 2025