UK Patent System: A Practical Guide | UKIPO Filing, 2026 Fee Changes, the Supreme Court's AI Patent Ruling, EP(UK) and the UPC

There are three ways to obtain a patent in the United Kingdom (UK): filing directly with the UK Intellectual Property Office (UKIPO), obtaining a European patent with a UK extension (EP(UK)) through the European Patent Office (EPO), and converting a PCT application into a UK national application.Even after leaving the EU, the United Kingdom remains a contracting state to the European Patent Convention (EPC), so it is important to avoid the misconception that “European patents are no longer valid in the UK due to Brexit.” However, the UK does not participate in the unitary patent (UP) or the Unified Patent Court (UPC).

In this article, based on the Patents Act 1977 and official guidance from the UKIPO, we outline the UK patent system—including application routes, procedural deadlines, the examination process, official fees revised in April 2026, and post-grant maintenance and enforcement.We will also explain the latest developments, including the shift in examination standards for AI and software patents following the Supreme Court ruling in February 2026 (the “Emotional Perception AI” case), as well as the “long-arm jurisdiction” under which the UPC extends its jurisdiction to cover infringements occurring in the UK. This content is intended for intellectual property professionals at companies with operations in the UK market or R&D centers in Europe.

1. Overview of the UK Patent System—Enabling Legislation, UKIPO, and the Impact of Brexit

The statutory basis for the UK patent system is the Patents Act 1977 and the Patents Rules 2007.The 1977 Act was enacted to bring the UK system into line with the European Patent Convention (EPC), and the patent requirements (novelty, inventive step, and industrial applicability) as well as the grounds for exclusion (Section 1(2)) are structured almost identically to those of the EPC.The governing authority is the UK Intellectual Property Office (UKIPO), headquartered in Newport, Wales. The Comptroller-General is responsible not only for examination and grant but also for quasi-judicial decisions, such as revocation proceedings (Section 72), declarations of non-infringement, and compensation for employee inventions (Section 40).

Brexit Had “Virtually No Impact” on Patents, Though the UK Will Not Participate in the Unified Patent Court (UPC)

The UK’s withdrawal from the EU in 2020 (Brexit) had a significant impact on trademarks and designs (the separation of EU trademarks and EU designs from the UK), but the impact on patents was limited. Since the EPO is not an EU agency, the UK remains a member of the EPC even after Brexit, and European patents continue to cover the UK.There has also been no change in the UK’s membership in the Paris Convention and the PCT.

However, in February 2020, the UK government announced that it would not participate in the unitary patent (UP) or the Unified Patent Court (UPC). The reason given was that the UPC Agreement is based on the application of EU law and the supervision of the Court of Justice of the European Union, which is incompatible with the spirit of Brexit.Consequently, the Unified Patent (UP), which came into effect in June 2023, does not extend to the UK, and obtaining rights in the UK will require either filing directly with the UKIPO or validating an EP(UK) under the traditional system.The mechanisms of the European patent and the UPC are explained in detail in “Practical Guide to the European Patent System: A Patent Attorney’s Comprehensive Explanation of the EPC, EPO, and UPC.”

2. Three Application Routes—Direct Filing with UKIPO, EP(UK), and PCT National Phase Entry

As a practical guideline, if you wish to obtain protection in only a few European countries, a direct application to UKIPO is recommended; if you wish to obtain protection in many countries, the EP(UK) route is more cost-effective. With the EP(UK) route, it is important to note that renewal fees after grant must be paid directly to UKIPO, and that you must have a UK address for service (discussed below) ready after grant.For an overview of the PCT route, please refer to the “Practical Guide to International Patent Applications (PCT).”

3. Application Requirements—Language, Address for Service, and Priority

The language is English; a power of attorney is generally not required

Application documents submitted to the UKIPO must be in English (or Welsh). While it is possible to secure a filing date using Japanese, the application will lapse unless an English translation is submitted within the prescribed period. As a general rule, a Power of Attorney is not required to appoint a representative, nor is notarization or an apostille necessary.For Japanese companies, this makes the process very straightforward, and the burden of preparing documents is among the lowest compared to other major countries.

Service of Process Addresses Are Limited to the UK, Gibraltar, the Channel Islands, and the Isle of Man

While appointing a representative is not a legal requirement, for applications filed on or after January 1, 2021, the UKIPO will not examine the application unless a service address within the UK, Gibraltar, the Channel Islands (and the Isle of Man) is provided.Prior to Brexit, an address within the European Economic Area (EEA) was sufficient, but EEA addresses are no longer accepted. The same applies when initiating litigation proceedings, such as revocation actions, before the UKIPO.In practice, it is standard procedure to designate a UK Chartered Patent Attorney as the address for service. For EP(UK) applications as well, a UK address for service is required when conducting post-grant proceedings with UKIPO.

Securing Priority and Filing Date

You can claim priority under the Paris Convention if you file within 12 months of the Japanese application. Since the Japan Patent Office and UKIPO are connected via WIPO’s Digital Access Service (DAS), a paper certificate is not required; simply providing the access code is sufficient.To secure the filing date, it is sufficient to identify the applicant and provide a “description of the invention”; claims, the abstract, and a request for search can be supplemented within 12 months of the filing date (priority date). This flexibility—securing the filing date first and finalizing the application later—is a hallmark of the UK system.

4. Examination Process and Deadlines—12 Months for Request for Search, 6 Months for Request for Examination, and the 4-Year-and-6-Month Rule

The UK examination process is divided into “search” and “substantive examination,” each of which requires a separate request and fee. Since the deadlines differ from Japan’s rule of “requesting examination within three years of filing,” please refer to the table below to understand the process.

Under normal circumstances, the process from filing to grant takes approximately 2 to 4 years. If a request for search and examination is filed simultaneously with the application, UKIPO can significantly expedite the grant process; when combined with an accelerated processing request, grant can reportedly be achieved in about 18 months.However, UKIPO itself acknowledges in its FY2026–27 plan that processing delays will occur during the transition period to the new system (One IPO Patent Service) in April 2026; therefore, caution is advised regarding fluctuations in examination waiting times for the time being.

5. Means of Early Grant—PPH, Green Channel, and Combined Search and Examination

• Combined Search and Examination: If you request both at the time of filing, the search report and the initial examination report are delivered together, and the examination proceeds before publication. No additional fees apply.
• Request for Accelerated Search/Examination: If you provide written justification—such as suspected infringement or the need to explain the invention to investors—the UKIPO will expedite the search, examination, and publication. Free of charge
• Green Channel: If you can reasonably argue that the invention offers environmental benefits, accelerated processing is granted without the need for detailed substantiation of the reasons. Introduced in 2009; free of charge. Covers a wide range of technologies, including energy conservation, recycling, and EV-related technologies
• PPH/Global PPH (GPPH): If you align your claims with those deemed patentable by the Japan Patent Office, UKIPO will expedite the examination. Free of charge. Conversely, a “UK-first” strategy is also possible, where you obtain a grant from UKIPO first and then use it for PPH in Japan or the U.S.
• PCT(UK) Fast Track: Acceleration is granted if a national phase application is filed based on claims for which patentability was affirmed in a report from an International Searching Authority or an International Preliminary Examination Report. Free of charge.

6. Patent Requirements and Grounds for Exclusion—Supreme Court Rulings on AI and Software Inventions

The requirements for patentability are novelty, inventive step, and industrial applicability; like the EPC, the standard is absolute novelty (worldwide prior art).Article 1(2) stipulates that discoveries, scientific theories, mathematical methods, aesthetic creations, mental activities, games, business methods, computer programs, and the presentation of information are not inventions “as such.” The interpretation of this phrase “as such” has determined the fate of AI and software inventions.

Emotional Perception AI Case (February 2026, Supreme Court) — Abolition of the Aerotel Test

For many years, the UK has determined whether an invention falls under an exclusion ground using a four-step test based on the 2006 Aerotel ruling (claim interpretation → identification of actual contribution → determination of whether it falls under an exclusion ground → determination of whether it has a technical nature).Unlike the EPO’s approach—which holds that “if hardware is involved, the application passes the threshold for inventiveness, and the technical contribution is evaluated in terms of inventive step”—the UK has rejected many software applications at the threshold, leading to divergent conclusions between Japan and Europe.

On February 11, 2026, in the Emotional Perception AI case—which involved a dispute over the patentability of a system that recommends music using artificial neural networks (ANNs)—the UK Supreme Court held that: (1) an ANN constitutes a “computer program” regardless of whether it is implemented in software or hardware;(2) however, the Aerotel test confuses the determination of inventiveness with that of novelty and inventive step and therefore cannot be applied; and (3) in line with the EPO’s “any hardware” approach, claims involving physical hardware possess a technical character and are not subject to the “as such” exclusion.The case has been remanded to the UKIPO and will be re-examined with regard to novelty and inventive step.

7. Fees—List of Official Fees Following the April 2026 Revision

On April 1, 2026, the UKIPO raised its official fees for patents, trademarks, and designs by an average of 25 percent.This is the first revision to patent fees since 2018. The main official fees after the revision (for online procedures) are as follows. Yen equivalents are shown based on an exchange rate of approximately 1 pound ≈ 200 yen (as of September 2026; exchange rates are subject to fluctuation).

The basic three-part package of filing, search, and examination totals £405 (approx. 80,000 yen), which is significantly cheaper than in Japan (filing fee: 14,000 yen + request for examination: 138,000 yen + additional claims fee), the U.S., or the EPO.The actual cost is determined by the UK agent’s fees and English translation costs; for direct filings with UKIPO, the total cost until grant is generally estimated at approximately 800,000 to 1,500,000 yen per application. For an EP (UK) that is a European patent in English, the cost of validation is effectively zero, and the patent can be maintained by paying only the renewal fees.

8. Post-Grant — Renewal, Revocation, Opinion Services, SPC, and Patent Box

Term of protection: 20 years; renewal fees begin in the fifth year

The term of protection is 20 years from the filing date. Renewal fees are payable annually starting from the fourth anniversary (the fifth year) of the filing date. The due date is the last day of the filing month; the standard payment period runs from three months before the due date to one month after it. Thereafter, a six-month grace period is available during which payment can be made with a surcharge of £32 per month.If this period is also missed, an application for “restoration” may be filed within a further 13 months, provided that evidence is submitted demonstrating that the non-payment was not intentional. Since EP(UK) renewal fees are paid directly to UKIPO rather than the EPO, it is necessary to manage the EPO’s notifications and the UK deadlines separately.

No pre-grant opposition; post-grant, there are requests for revocation and the “Opinion Service”

The United Kingdom does not have a pre-grant or immediate post-grant opposition system similar to Japan’s patent opposition or the EPO’s opposition proceedings. The only actions available to third parties are the submission of information after publication but before grant (Article 21) and requests for revocation after grant (Article 72).A request for revocation may be filed with either the UKIPO (the Director General) or a court, and anyone may file such a request at any time.

A system unique to the UK is the UKIPO Opinion Service (Section 74A). For £250, anyone can obtain a non-binding opinion from a UKIPO examiner—typically within three months—regarding the validity of a specific patent (novelty, inventive step, and written description requirements) or whether infringement has occurred.This service is used to assess prospects prior to litigation, as a basis for licensing negotiations, and to provide grounds for rebutting cease-and-desist letters; if an opinion negating validity is issued, the UKIPO may initiate revocation proceedings on its own initiative. As it allows for a third-party perspective at a low cost, this system is also easy for Japanese companies to utilize.

SPCs and the Patent Box

For pharmaceuticals and pesticides, the Supplementary Protection Certificate (SPC) system—which incorporates EU regulations into domestic law—remains in place even after Brexit, allowing for an extension of up to five years (plus six months for pediatric medicines).In terms of taxation, the Patent Box scheme reduces the corporate income tax rate to an effective 10% on profits derived from patents granted by UKIPO or the EPO (including patents from certain EEA countries).This is contingent on a subsidiary paying corporate income tax in the UK holding or being licensed to use the patent and being involved in its development; for Japanese companies with R&D and manufacturing bases in the UK, this serves as a significant incentive to obtain UK patents.

9. Enforcement of Rights—Long-Arm Jurisdiction of the Patents Court, IPEC, and UPC

Two Courts of First Instance—the Patents Court and IPEC

There are two courts of first instance for patent infringement litigation: the Patents Court of the High Court and the Intellectual Property Enterprise Court (IPEC), which handles smaller-scale cases.IPEC handles cases with claims of £500,000 or less, and the maximum litigation costs recoverable from the opposing party are capped at £60,000 for liability proceedings and £30,000 for damages proceedings.Hearings are conducted in a concentrated format lasting one to two days, creating a system that allows small and medium-sized enterprises and foreign companies to enforce their rights in a way where “even if they lose, the costs are predictable.” There is also a small claims track for cases with claims of £10,000 or less. Appeals proceed to the Court of Appeal and, subsequently, to the Supreme Court.While UK courts apply strict standards when assessing patent validity—and are known within Europe as a jurisdiction where patents are “easily invalidated”—their detailed reasoning in judgments exerts influence on litigation in other countries as well.

The UPC’s “Long-Arm Jurisdiction”—Not Irrelevant Even for Non-Participants

The February 2025 judgment of the Court of Justice of the European Union in BSH v. Electrolux recognized that courts in EU member states may rule on infringements of patents from non-EU countries (including the UK) based on the defendant’s place of residence.In response, the UPC recognized jurisdiction over infringement of an EP(UK) patent in the January 2025 Fujifilm v. Kodak case (Düsseldorf Regional Court), and in August 2025, the Mannheim Regional Court issued the UPC’s first injunction covering the UK portion of the claim.The conditions include that the defendant be domiciled in a UPC member state and that no parallel invalidation proceedings be pending in the UK.

10. Latest Statistics and Developments in 2026—Surge in Applications and One IPO’s New Service

In 2025, while the number of applications from within the UK surged to its highest level in 10 years, the number of grants fell by more than 30 percent.On April 1, 2026, UKIPO launched its new online patent service, “One IPO,” transitioning to a system that allows users to file, manage, and renew applications centrally through verified user accounts; however, the UKIPO has explicitly noted processing delays associated with the migration from the old system in its fiscal year 2026–27 plan.Applications from foreign applicants are on a downward trend; for Japanese companies seeking to secure rights in the UK, strategically choosing between the EP (UK) route and utilizing expedited procedures are practical measures to address examination delays.

11. Comparison with the Japanese Patent System

12. Checklist of Practical Considerations

• Decide on the route first. If applying only to the UK or to two or three countries, file directly with the UKIPO. If applying to four or more European countries, file an EP (UK). An English-language European patent does not require translation or validation procedures in the UK
• Secure an address for service (UK, Gibraltar, Channel Islands, or Isle of Man). An EEA address is not acceptable. This is also required for post-grant procedures for EP(UK).
• Record the two-stage deadlines—12 months for a request for search and 6 months for a request for examination—in your records. Do not manage these deadlines based on the Japanese “3-year” mindset
• Design claims with the 4-year-and-6-month patent examination period in mind. If grounds for rejection are likely to persist, consider filing a divisional application early
• Acceleration options are free of charge. If the patent has been granted in Japan, use the GPPH; for environment-related inventions, use the Green Channel; and file a request for acceleration if there is a compelling reason to expedite the process.
• For AI and software inventions, in light of the 2026 Supreme Court ruling, clearly define the technical problem and effect in the specification. While the entry requirements have become less stringent, the invention will still be scrutinized for inventive step
• Renewal fees are paid directly to UKIPO. For EP(UK) applications, payments are made to UKIPO, not the EPO. Starting in the fifth year, a 6-month grace period applies (with a £32 monthly surcharge).
• Since there are no oppositions, assess the validity outlook of competing patents using an opinion service (£250) and file a request for revocation if necessary.
• Be aware of the UPC’s long-arm jurisdiction. Companies with a presence within the EU may be subject to injunctions in the UPC regarding EP(UK) patents as well. Defendants can counter this by filing early invalidation proceedings in the UK
• If you have a base in the UK, consider the Patent Box. Corporate tax is 10% on profits from UK and EP patents. Coordinate with the tax department from the application stage onward

13. Frequently Asked Questions (FAQ)

Q1. After Brexit, can a European patent (EPO application) cover the UK?

Yes. The EPO is not an EU institution, and the UK remains a signatory to the European Patent Convention. An English-language European patent automatically becomes a UK patent upon grant, requiring neither translation nor a validation procedure. However, unitary patents do not extend to the UK.

Q2. What is the deadline for requesting examination of a UK patent?

A request for search must be filed within 12 months of the priority date (or the filing date if no priority date is claimed), and a request for substantive examination must be filed within 6 months of the publication of the application. Both requests can be filed simultaneously at the time of application; in that case, the examination process begins before publication.

Q3. How much are the official fees for obtaining a patent in the UK?

Following the revision effective April 1, 2026, the basic fees total £405 (approximately 80,000 yen), consisting of a filing fee of £75, a search request fee of £200, and a request for substantive examination fee of £130.Renewal fees increase in stages from £90 in the fifth year to £810 in the twentieth year, with a total of £6,160 for 20 years. Attorney fees and translation costs are charged separately.

Q4. What is the “4-year-and-6-month rule”?

This is the deadline by which the application must be brought into a patentable condition within 4 years and 6 months from the priority date (or 12 months from the date the first examination report was sent, whichever is later); otherwise, the application is deemed to have been rejected. While extensions in 2-month increments are possible, they are not unlimited; therefore, for cases where examination takes a long time, planning—including the possibility of divisional applications—is necessary.

Q5. Can inventions involving AI or software be patented in the UK?

They can. In a February 2026 Supreme Court ruling (the Emotional Perception AI case), the traditional Aerotel test was abolished, and the UK shifted to the same approach as the EPO: “inventions are not excluded at the outset if they involve hardware.”However, since the technical contribution is examined at the stage of determining inventive step, it remains crucial to clearly articulate the technical problem and the solution in the specification.

Q6. Since the UK is not a member of the UPC, are UPC rulings irrelevant to the UK?

No, it is not irrelevant. Since the 2025 European Court of Justice ruling in BSH v. Electrolux, the UPC has been ruling on infringements of the UK portion of European patents and issuing injunctions against defendants with addresses in UPC member states. Companies with a presence within the EU may be sued in the UPC regarding UK patents as well.

14. Summary

The UK patent system is characterized by five key features: (1) “low barriers to entry,” such as no need for a power of attorney, low official fees, and free accelerated processing; (2) “unique time limits,” including a 12-month period for filing a request for search, a 6-month period for filing a request for examination, and a total examination period of 4 years and 6 months; (3) the absence of opposition proceedings, replaced by revocation actions and an opinion service;④ an examination process for AI and software that aligns more closely with the EPO following a 2026 Supreme Court ruling; and ⑤ the fact that, despite not participating in the UP or UPC, the UPC’s long-arm jurisdiction extends to the UK—these five points.By choosing between direct applications to UKIPO and EP(UK) based on the number of European countries covered, ensuring proper management of UK service addresses and deadlines, and clearly describing the technical effects of AI inventions—if you keep these three points in mind, the UK is a cost-effective jurisdiction for Japanese companies to secure intellectual property rights.

Recommended Reading

• Practical Guide to the European Patent System | A Patent Attorney’s Comprehensive Explanation of the EPC, EPO, and UPC
• Practical Guide to the German Patent System | A Patent Attorney’s Comprehensive Explanation of the DPMA, BPatG, EPO, the Unified Patent (UPC), and Dual Litigation
• Overview of the UK Trademark System
• Overview of the UK Design System
• Practical Guide to International Patent Applications (PCT)

Sources and References

• Patents Act 1977 (legislation.gov.uk): https://www.legislation.gov.uk/ukpga/1977/37
• Manual of Patent Practice – Section 20 (Patent Examination Time Limits) (GOV.UK): https://www.gov.uk/guidance/manual-of-patent-practice-mopp/section-20-failure-of-application
• Renew a patent (GOV.UK): https://www.gov.uk/renew-patent
• Patents: Accelerated Processing (GOV.UK): https://www.gov.uk/guidance/patents-accelerated-processing
• Address for service for intellectual property rights (GOV.UK): https://www.gov.uk/guidance/address-for-service-for-intellectual-property-rights
• Facts and figures: patents, trademarks, designs, and hearings 2025 (GOV.UK):https://www.gov.uk/government/publications/facts-and-figures-patents-trade-marks-designs-and-hearings-2025/facts-and-figures-patents-trade-marks-designs-and-hearings-2025
• Intellectual Property Office Corporate Plan 2026–2027 (GOV.UK):https://www.gov.uk/government/publications/intellectual-property-office-corporate-plan-2026-to-2027/intellectual-property-office-corporate-plan-2026-to-2027
• Corporation Tax: the Patent Box (GOV.UK): https://www.gov.uk/guidance/corporation-tax-the-patent-box
• Fee increases at the UKIPO effective April 1, 2026 (Hindles): https://www.hindles.co.uk/content/fee-increases-at-the-ukipo-from-1-april-2026
• Emotional Perception AI Ltd v Comptroller General [2026] UKSC 3 (UK Supreme Court): https://supremecourt.uk/cases/uksc-2024-0131
• Focusing on long-arm jurisdiction: the UPC grants its first injunction covering the UK (Kluwer Patent Blog):https://legalblogs.wolterskluwer.com/patent-blog/focussing-in-on-long-arm-jurisdiction-the-upc-grants-first-injunction-covering-the-uk/
• Impact of the UK’s Withdrawal from the EU (Brexit) on Patents, Trademarks, Designs, etc. (Japan Patent Office): https://www.jpo.go.jp/system/laws/gaikoku/uk/brexit_202002.html

*This article was prepared as of September 2026 for general informational purposes, based on the 1977 Patents Act, official guidance and statistics from UKIPO (GOV.UK), the 2026–27 annual plan, Supreme Court rulings, and publicly available materials from local law firms.Office fees, exchange rates, and examination periods are subject to change. We recommend consulting with a professional for specific decisions regarding individual cases.

AUTHOR / Author

Takefumi Sugiura (SUGIURA Takefumi)

EVORIX Intellectual Property Firm, Managing Patent Attorney

Assists clients across a wide range of industries—including IT, manufacturing, startups, fashion, and healthcare—with everything from patent, trademark, design, and copyright applications to appeals and infringement litigation.He is also well-versed in intellectual property strategies for cutting-edge fields such as AI, IoT, Web3, and FinTech. He is a member of several organizations, including the Japan Patent Attorneys Association, the Asian Patent Attorneys Association (APAA), and the Japan Trademark Association (JTA).

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