Thaler v Comptroller-General of Patents, Designs and Trade Marks [2023] UKSC49.

Case Summary

Case Citation and Basic Information

Case name: Thaler v Comptroller-General of Patents, Designs and Trade Marks [2023] UKSC 49.

Court: Supreme Court of the United Kingdom.

Date of decision: 20 December 2023.

Bench composition: Lord Hodge (Deputy President), Lord Kitchin (lead judgment), Lord Hamblen, Lord Leggatt and Lord Richards JJSC.

Parties: Stephen L Thaler (Appellant); Comptroller-General of Patents, Designs and Trade Marks (Respondent); Chartered Institute of Patent Attorneys (Intervener).

Introduction

This appeal concerns whether an artificial intelligence (AI) system can be named as the ‘inventor’ of a patentable invention under the Patents Act 1977.[1] Dr Stephen Thaler, owner of an AI machine called DABUS, filed two UK patent applications asserting that DABUS had autonomously devised the inventions and that his ownership of the machine entitled him to obtain the resulting patents. The UK Supreme Court unanimously dismissed his appeal, holding that an inventor under English patent law must be a natural person. The judgment aligns with parallel decisions rejecting AI inventor status before the United States Federal Circuit and the European Patent Office,[2] producing a consistent international position at a pivotal moment for artificial intelligence and intellectual property law.

III. Facts of the Case

In October and November 2018, Dr Thaler filed two UK patent applications: one for a food container with a fractal surface design and another for an emergency light beacon. Both applications stated that Dr Thaler was not himself the inventor; instead he identified DABUS (Device for the Autonomous Bootstrapping of Unified Sentience), an AI machine of which he was sole owner, as having devised both inventions entirely autonomously. Dr Thaler claimed entitlement to the patents purely by virtue of owning the machine.

The UK Intellectual Property Office (UKIPO) required Dr Thaler to file statements of inventorship under section 13(2) of the Patents Act 1977,[3] identifying the person believed to be the inventor and indicating how the applicant derived the right to apply. Dr Thaler’s statements named DABUS as inventor. The UKIPO held that this did not satisfy section 13(2), since DABUS is not a person capable of being an inventor, and the applications were treated as deemed withdrawn under rule 10(3) of the Patent Rules 2007[4] upon expiry of the prescribed sixteen-month period.

Dr Thaler’s appeal to the High Court was dismissed by Marcus Smith J in 2020.[5] A further appeal to the Court of Appeal was dismissed by a 2:1 majority:[6] Arnold LJ and Elisabeth Laing LJ held that an inventor must be a natural person, while Birss LJ dissented on the basis that the formal requirements of section 13(2) had been met by Dr Thaler’s honest statement of belief.[7] Dr Thaler then appealed to the Supreme Court, with the Chartered Institute of Patent Attorneys intervening in his support. It was accepted throughout that DABUS had generated the two inventions autonomously.

Legal Issues

Issue 1: Whether the term ‘inventor’ in sections 7 and 13 of the Patents Act 1977 can extend to a non-human AI machine such as DABUS.

Issue 2: Whether Dr Thaler was nonetheless entitled to apply for and obtain patents for the advances generated by DABUS purely on the basis of his ownership of the machine.

Issue 3: Whether the Comptroller-General was entitled to treat the two applications as deemed withdrawn for failure to comply with section 13(2) of the Patents Act 1977.

Arguments Presented

5.1 Appellant’s Arguments (Dr Thaler)

Dr Thaler, represented by Robert Jehan and Professor Ryan Abbott, contended that he was entitled to apply for patents for inventions generated by DABUS, and that the owner of an AI system ought to be recognised as entitled to its outputs. He argued that section 13(2) required only an honest statement of belief as to the inventor’s identity, which he had satisfied by naming DABUS, and that the Comptroller had no basis to look behind that statement. In the alternative, Dr Thaler relied on the common law doctrine of accession, arguing that his ownership of DABUS gave him a derivative proprietary right over all technical advances it generated, sufficient to support an application under section 7(2)(b).

5.2 Respondent’s Arguments (Comptroller-General)

The Comptroller-General maintained that ‘inventor’ under sections 7 and 13 means the natural person who actually devised the invention, relying on the House of Lords’ analysis in Yeda Research and Development Co Ltd v Rhone-Poulenc Rorer International Holdings Inc,[8] which confirmed that an inventor must be a natural person and that any grantee must claim through that inventor. Since DABUS had no legal personality, Dr Thaler could derive no right through it, and the doctrine of accession had no application to intangible inventive concepts.

Court’s Reasoning and Analysis

Lord Kitchin, giving the unanimous judgment, emphasised that the appeal was confined to the correct interpretation of the Patents Act 1977 as it stands. The broader policy question of whether AI-generated advances ought to be patentable in principle, and whether the definition of ‘inventor’ should be expanded, were matters for Parliament rather than the Court.[9]

On Issue 1, the Court held that section 7(3) of the 1977 Act[10] defines ‘inventor’ as ‘the actual deviser of the invention’, a term which, read in context, can only refer to a natural person. In Yeda Research, Lord Hoffmann confirmed that the inventor must be the natural person who devised the inventive concept,[11] and that section 7(2) provides an exhaustive code permitting grant only to the inventor or to a person deriving title through them.[12] Since DABUS was accepted to have generated the technical advances entirely autonomously, it could not satisfy this definition.[13]

On Issue 2, the Court rejected the accession argument. The doctrine applies to new tangible property produced from existing tangible property and has no application to intangible inventive concepts. More fundamentally, since DABUS could never be an inventor, there was no inventor through whom Dr Thaler could derive any entitlement. Ownership of the machine that generated a technical advance conferred no property right in that advance. The Court agreed with the Court of Appeal that, if patents were to be granted for machine-generated inventions, the 1977 Act would require amendment.[14]

On Issue 3, the Court held that Dr Thaler had failed to satisfy either limb of section 13(2), having neither identified a person believed to be the inventor nor indicated how he derived the right to apply. The applications were therefore correctly treated as withdrawn, and the Court rejected Birss LJ’s view that honest assertion of a legally impossible belief could satisfy section 13(2).[15]

VII. Judgment and Ratio Decidendi

The Supreme Court unanimously dismissed the appeal and confirmed that both patent applications were correctly deemed withdrawn under rule 10(3) of the Patent Rules 2007.[16] No further orders were issued.

The ratio decidendi is that, under sections 7 and 13 of the Patents Act 1977, an ‘inventor’ must be a natural person who actually devised the invention; a machine, however autonomously it generates a technical advance, cannot be an inventor, and mere ownership of that machine does not of itself confer any right to apply for or obtain a patent for what it produces.

VIII. Critical Analysis

8.1 Significance of the Decision

The judgment is the United Kingdom’s authoritative answer to a question arising across multiple jurisdictions as AI systems increasingly produce outputs that would satisfy patentability requirements if generated by a human. By confining its reasoning to statutory interpretation, the Court deliberately left to Parliament the question of whether AI-generated advances should in principle attract patent protection. This mirrors the approach of the United States Federal Circuit and the European Patent Office,[17] producing a consistent international position that existing patent systems require a human inventor and providing practitioners with clear, if uncomfortable, guidance.

8.2 Implications and Impact

The decision means that inventions substantially generated by autonomous AI systems may fall outside patent protection in the United Kingdom unless a natural person can properly be identified as inventor — for example by exercising inventive judgment in directing the AI’s output rather than merely owning the machine. This risks weakening the incentive to invest in and disclose AI-driven innovation, undermining the public-disclosure function at the heart of the patent system. Broader questions also arise as to how legal frameworks premised on human agency should accommodate outputs produced by systems lacking legal personality.

8.3 Critical Evaluation

The Court’s textual reasoning is difficult to fault as a matter of statutory construction: the 1977 Act plainly contemplates a human deviser, and the rejection of the accession analogy is equally persuasive. However, the decision exposes a legislative gap rather than closing it. By declining to reformulate ‘inventor’, the Court leaves open how the patent system should accommodate autonomous AI contributions. Birss LJ’s dissent usefully illuminated the tension between the Act’s low evidentiary bar for inventorship statements and the substantive requirement that any named inventor be legally capable of holding that status.[18] As AI capabilities advance, this judgment will likely serve as the catalyst for legislative reform rather than the final word.

Conclusion

Thaler v Comptroller-General of Patents, Designs and Trade Marks firmly establishes that, under the Patents Act 1977, only a natural person can be recognised as an inventor, and that ownership of an autonomous AI machine does not of itself generate any right to patent what it produces. As AI systems grow more capable of generating novel technical advances with diminishing human input, pressure will grow on Parliament to reform the patent system accordingly. For now, applicants seeking UK patent protection for AI-assisted inventions must ensure a human inventor can properly be identified. The judgment stands as a clear and authoritative marker of the limits of existing intellectual property law in the face of increasingly autonomous artificial intelligence.

Reference(S):

Legislation

Patents Act 1977.

Patent Rules 2007 (SI 2007/3291).

Cases

Thaler v Comptroller-General of Patents, Designs and Trade Marks [2023] UKSC 49.

Thaler v Comptroller-General of Patents, Designs and Trade Marks [2021] EWCA Civ 1374, [2022] Bus LR 375.

Thaler v Comptroller-General of Patents [2020] EWHC 2412 (Pat), [2020] Bus LR 2146.

Yeda Research and Development Co Ltd v Rhone-Poulenc Rorer International Holdings Inc [2007] UKHL 43, [2007] Bus LR 1796.

University of Southampton’s Applications [2004] EWHC 2107 (Pat), [2005] RPC 220.

Nippon Piston Ring Co Ltd’s Applications [1987] RPC 120.

Thaler v Vidal 43 F 4th 1207 (Fed Cir 2022), cert denied 143 S Ct 1783 (2023).

EPO Legal Board of Appeal, Decision J8/20 (21 December 2021).

Secondary Sources

D Young & Co, ‘UK Supreme Court Rules Only People Can Be Named as Patent Inventors’ (9 February 2024) <https://www.dyoung.com/en/knowledgebank/articles/supreme-court-patents-ai-only-people-inventors> accessed 30 June 2026.

Kluwer Patent Blog, ‘The End of the Road for DABUS and Dr Thaler at the UK Supreme Court’ (16 January 2024) <https://legalblogs.wolterskluwer.com/patent-blog> accessed 30 June 2026.

White & Case, ‘UK Supreme Court Rules Against AI Inventorship of Patents’ (28 December 2023) <https://www.whitecase.com/insight-our-thinking/uk-supreme-court-rules-against-ai-inventorship-patents> accessed 30 June 2026.

[1]Thaler v Comptroller-General of Patents, Designs and Trade Marks [2023] UKSC 49 (hereafter Thaler).

[2]Thaler v Vidal 43 F 4th 1207 (Fed Cir 2022), cert denied 143 S Ct 1783 (2023); EPO Legal Board of Appeal, Decision J8/20 (21 December 2021).

[3]Patents Act 1977 (hereafter PA 1977), s 13(2).

[4]Patent Rules 2007 (SI 2007/3291), r 10(3).

[5]Thaler v Comptroller-General of Patents [2020] EWHC 2412 (Pat), [2020] Bus LR 2146.

[6]Thaler v Comptroller-General of Patents, Designs and Trade Marks [2021] EWCA Civ 1374, [2022] Bus LR 375.

[7]ibid paras 35–102 (Arnold LJ and Elisabeth Laing LJ); paras 106–136 (Birss LJ, dissenting).

[8]Yeda Research and Development Co Ltd v Rhone-Poulenc Rorer International Holdings Inc [2007] UKHL 43, [2007] Bus LR 1796 (hereafter Yeda Research).

[9]Thaler (n 1) para 48.

[10]PA 1977 (n 3) s 7(3).

[11]Yeda Research (n 8) para 20, approving Laddie J in University of Southampton’s Applications [2004] EWHC 2107 (Pat), [2005] RPC 220.

[12]Yeda Research (n 8) para 18.

[13]Thaler (n 1) para 56.

[14]Thaler (n 1) para 79, approving Elisabeth Laing LJ in Thaler (n 6) para 103: ‘Whether or not thinking machines were capable of devising inventions in 1977, it is clear to me that Parliament did not have them in mind when enacting this scheme.’

[15]Thaler (n 1) paras 91–98.

[16]Patent Rules 2007 (n 4) r 10(3).

[17]Thaler v Vidal (n 2); EPO Decision J8/20 (n 2).

[18]Thaler [2021] EWCA Civ 1374 (n 6) paras 106–136 (Birss LJ, dissenting).