Invention - Exclusions from patentability - Computer implemented method of designing drill bits

Re: patent application in the name of Halliburton Energy Services Inc and others: ChD (Patents Court) (Judge Birss QC sitting as a judge of the High Court): 5 October 2011

The claimant company invented methods of improving the design of roller cone drill bits used in drilling wells. The inventions used a computer simulation of the interaction of the drill bit with the material being drilled to optimise various design features on the drill bits.

The claimant made four patent applications to the UK Intellectual Property Office. Those were rejected on the basis that the inventions were excluded from patentability as schemes, rules or methods for performing a mental act under section 1(2)(c) of the Patents Act 1977 (the mental act exclusion), and as computer programs. The claimant appealed.

The issue was whether the judge had applied the correct construction of the mental act exclusion. The appeals would be allowed.

There were two possible interpretations of the mental act exclusion, a wide one and a narrow one. The wide construction held that a claim was a scheme, rule or method for performing a mental act if it was capable of being performed mentally regardless of whether or not it was in fact performed mentally. The narrow construction held that the exclusion only applied to acts actually 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 did not encompass carrying out the calculation mentally. The fact that calculations in general were the kinds of thing which were capable of being performed as mental acts was irrelevant. The balance of authority in England was in favour of the narrow approach (see [42]-[43], [57] and [63] of the judgment).

The narrow approach to the mental act exclusion was correct because the purpose of the exclusion was to make sure that patent claims could not be performed by mental means, that was all (see [63] of the judgment).

In the instant case, when the judge applied the mental act exclusion he did so on too broad a basis and his decision was ill-founded. The claimed method of designing drill bits was a computer-implemented method that could not be performed by mental means, and so could not fall within the mental act exclusion. The method was clearly more than just a computer program as it was a method for designing drill bits, and drill-bit design was not, in the instant case, a scheme for performing a mental act (see [64] and [70]-[71] of the judgment). The cases would be remitted to the comptroller (see [80] of the judgment).

Per curiam: The approach proposed to mental acts in paragraph 8 of the current guidance, the comptroller’s practice note issued on 2 November 2006, and which encouraged examiners to follow the wide construction of the mental act exclusion, was wrong in law and should not be followed (see [78] of the judgment).

Richard Davis (instructed by Hoffmann Eitle) for the claimant; Thomas Mitcheson (instructed by the Treasury Solicitor) for the defendant.