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UK High Court takes a narrow view of mental act exclusion

1st Nov 2011

Following a recent decision of the England and Wales High Court, in Halliburton Energy Services Inc, see here, UK Intellectual Property Office (UK-IPO) Examiners “…will now be required to take a narrow view of the mental act exclusion in UK Patent Law. In doing so, the UK-IPO has once again been compelled by the courts to take a more lenient approach to computer implemented inventions and other subject matter held to be intrinsically ‘non-patentable’.

The Halliburton cases related to a method of designing a drill bit using a computer simulation. In line with current patent practice, Halliburton’s applications had been refused by the UK-IPO on the grounds that the method was both an excluded mental act and an excluded computer program, set out under Section 1(2) of the UK Patents Act.

The initial UK-IPO positioned seemed justified: the claimed subject matter not only failed to recite any hardware (other than the drill bit being designed), it also neglected to include a “step of manufacturing a drill bit to the design”. Notwithstanding the complexity of the method claimed therefore, the claim features appeared simply to define the solely mental steps of designing, simulating and modifying design parameters, without those features being directly linked to a tangible product (in this case all that resulted from performing the method was a design).

In wrestling with these issues, the High Court conducted a review of the UK case law (including the seminal Aerotel & Macrossan and Fujitsu decisions) and observed that:

“there are essentially two possible interpretations of this [mental act] exclusion, a wide one and a narrow one. The wide construction is that a method is “a scheme, rule or method for performing a mental act” if it is capable of being performed mentally regardless of whether, as claimed, it is in fact performed mentally.”

“The narrow construction is that the exclusion only excludes acts carried out mentally. On the narrow construction a claim to a calculation carried out on a computer could never be caught by the mental act exclusion because the claim does not encompass carrying out the calculation mentally. The fact that calculations in general are the kinds of thing which are capable of being performed as mental acts is irrelevant”.

As noted above, the UKIPO has traditionally followed the wide construction, meaning that:

“a claim to a computer programmed to carry out a method of performing a calculation (say a square root), would not only be caught by the computer program and mathematical method exclusions but would also be excluded by the mental act exclusion because calculations are the kind of thing which are capable of being performed mentally.”

However, on the basis of their review in Halliburton, the High Court construed the mental act exclusion narrowly, and ruled that the UK IPO had taken the exclusion too far. “Approached on the correct, narrow basis”, the method claimed in Halliburton was not caught under the exclusion as “the claimed method cannot be performed by purely mental means” or “Put another way, the contribution is a computer implemented method and as such cannot fall within the mental act exclusion”.

The Halliburton decision therefore puts the mental act exclusion squarely on its proper footing, bringing it back into line with the general maxim that exclusions in law should be construed narrowly. Further, it reveals once again that the UK courts are prepared to take a more progressive approach to computer implemented inventions than the UK-IPO. In both the Aerotel and Symbian decisions for example, the UK-IPO’s refusal of a computer implemented invention was overturned by the Courts.

The Computer Program Exclusion

Mental act exclusions are often relied upon the UK-IPO as only one half of a double-pronged rejection, comprising an objection that a claimed invention is both an excluded mental act and an excluded computer program. Without addressing the second computer program exclusion, therefore Halliburton’s position would not have been greatly improved by the High Courts interpretation of the meaning of the mental act exclusion. However, once again, the Court took the view that the invention in Halliburton was allowable.

The High Court did note that the fact that the invention was held to be not a mental act but a computer implemented method: “does not mean it is necessarily immune from the computer program exclusion”. However, in deciding on whether the subject matter of the case is excluded from patentability the question “Is it more than an [excluded] computer program as such?” should still be addressed. Here, the court held that:

The answer is plainly yes. It is a method of designing a drill bit. Such methods are not excluded from patentability by Art 52/S1(2) and the contribution does not fall solely within the excluded territory. Drill bit design is not a business method, nor a scheme for playing a game nor (as I have held) is this claim a scheme for performing a mental act.

The Court in Halliburton therefore found that the claimed method of designing a drill bit was neither an excluded mental act, because the method involves a computer and could not in any case be carried our by a person carrying out the calculations in their head, nor an excluded computer program as such, because it is plainly a method of designing a drill bit. In reaching this conclusion, the Court carefully navigated a path between the existing case law, but also taken a clear stand in opposition to a sometimes overly formulaic view of existing practice.

While the Court’s decision in Halliburton is encouraging and suggestive of a more favourable, less prescriptive approach to the interpretation of the patentable subject matter exclusions, only time will tell as to whether the patent landscape in the UK has really changed. Although, the UK-IPO has already issued a practice note, see here, reflecting the decision in Halliburton, patent practioners expect the UK-IPO to carry on taking a strict line against patent applications in this area, relying instead on the other exclusions set out under Section 1(2) rather than the mental act exclusion.

This article is for general information only. Its content is not a statement of the law on any subject and does not constitute advice. Please contact Reddie & Grose LLP for advice before taking before any action in reliance on it.

Nick Reeve
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Robert Sackin
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Would you like to know more? You can talk to Nick Reeve who will be able to help. Call +44 (0)20 7242 0901


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