Kitchin J., sitting in the High Court in the case of Astron Clinica ruled last Friday that the Court of Appeal's decision in Macrossan/Aerotel does not prohibit the patenting of a computer program, provided it delivers a relevant technical contribution. He considered the UK IPO's approach since Macrossan of rejecting all computer program claims as erring in law.

Business Impact

This decision re-asserts the principle of substance over form when considering patentability of computer programs. It also gives a clear message to the UK IPO that their current interpretation of Macrossan1 is not correct when it comes to program claims.

This ruling will be a boost to potential patentees of computer program claims, to whom it is often the actual computer program, rather than the method, which confers the commercial advantage. If followed, the ruling will also have the benefit of bringing the practice in the UK courts, EPO and the UK IPO in relation to the patentability of computer programs closer into line.


On 27th October 2006, we reported that the scope of the exclusions from patentability (including that of computer programs) had been clarified to a large extent by the decision in Macrossan, which laid down a four stage test for patentability. Though this approach was expressly rejected by the EPO in Duns Licensing Associates on the grounds that the European Patent Convention (EPC) encodes no concept of 'technical contribution', it has been adopted by the UK IPO but interpreted to mean that claims to computer programs (or a computer program on a carrier) are excluded from patentability.

The facts

The appeal concerned five applicants and six different patent applications for computer programs, including a method for generating higher quality images from laser printers, an invention to improve the ability of mobile telephones to access internet services and methods of identifying groups of target proteins for drug therapy. All the inventions are exploited by selling computer programs stored on a carrier of some sort or by internet download.

In each case the Examiner had allowed method and apparatus claims, but both the Examiner and the Hearing Officer found the corresponding claims to the computer programs themselves were not allowable. Without a patent to the programs, the patentees have only limited recourse (via the contributory infringement provisions of section 60(2) Patents Act 1977) against competitors who sell, produce or market similar products in the UK, and no protection against the sale of programs in the UK if they are intended for use abroad.

The law

The Court affirmed the Macrossan test, originally proposed by the UK IPO, as the correct test to be adopted by the UK IPO and UK Courts when considering the exclusions from patentability set out in Article 52 of the EPC. The four stages of the test are:

  1. Properly construe the claim – you have to decide what the monopoly is before going on to question whether it is excluded;
  2. Identify the actual contribution – what has the inventor really added to human knowledge?;
  3. Ask whether it falls solely within the excluded subject matter;
  4. Check whether the actual or alleged contribution is actually "technical" in nature.

The decision

The Hearing Officer, citing the UK IPO's practice note2 published as a result of Macrossan, had held that such claims in a computer program would not satisfy the Macrossan test on the grounds that,

"if the monopoly does not go beyond the program, the contribution is unlikely to go beyond "a program for a computer". Accordingly … few claims to programs in themselves will pass the third test."

Kitchin J. ruled that the decision in Macrossan did not prohibit the patenting of all computer programs and that the Hearing Officer had erred in law in finding the program claims were necessarily prohibited by Article 52(2). He considered the following points to be material:

  • The particular point did not arise in Macrossan – "the Court was not required to consider what claims were permissible in the case of a computer related invention which made a contribution extending beyond excluded subject matter";
  • He saw nothing in Macrossan which suggested that all computer programs were necessarily excluded by Art 52;
  • The test in Macrossan had been formulated as a re-ordering of previous UK authorities and therefore, in any particular case, the application of this approach should produce the same result as did the old; and
  • A desire to be consistent with the decisions of the EPO Board of Appeal/ German Supreme Court as far as possible. In particular he felt the EPO decision in IBM/Computer Program Product 3 to be persuasive but was unable to follow the "trio"4 of cases criticised in Macrossan and identified by Jacob LJ as conflicting with other EPO decisions.

The Judge found Macrossan to be authority for the approach that claims to computer-related inventions must be considered as a matter of substance not form - what is needed to make an excluded thing patentable is a relevant technical contribution.

"If a program makes a conventional computer operate in a new way so as to deliver a relevant technical contribution then it seems to me to be wholly artificial to say that the effect is delivered by the computer but not the program."

The appeals were, therefore, allowed and the cases remitted back to the UK IPO for further consideration.


This decision affirms the Macrossan test as the starting point for the UK courts and UK IPO when considering exclusions from patentability. It also offers some reassurance to patentees that, if they have a valid method claim for a computer implemented invention then a corresponding claim in the program will be allowable. That said, it remains to be seen how the UK IPO will amend their practise as a result of this decision.