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Patents: UK court ruling on computer-simulated design methods



United Kingdom

Patents: UK court ruling on computer-simulated design methods

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The UK High Court has recently ruled that a patent claim for a method of designing a drill bit using computer simulation is patentable. 

Under the UK’s Patents Act 1977, certain types of invention are not patentable.  Among the excluded inventions are any scheme, rule or method for performing a mental act.  In the past, the courts’ approach to this exclusion has been inconsistent.  Two separate Court of Appeal judgments have reached different conclusions.  In one case (Fujitsu Limited’s Application [1997] RPC 608), the Court of Appeal gave the exclusion a wide meaning.  It said that methods for performing anything capable of being performed mentally were excluded and not patentable.  The UK Intellectual Property Office (UKIPO), the body responsible for the administration of patent applications, followed Fujitsu in its practice, objecting to applications for computer implemented methods for the performance of anything capable of being performed mentally. 

In a judgment issued on 5 October 2011, the High Court rejected this approach.  The court said that it favoured an alternative, narrow  meaning given by the Court of Appeal in joined cases known as Aerotel v Telco / Macrossan’s Application [2007] RPC 7.  Under this narrow meaning, the exclusion only applies if the claim is for a method actually carried out mentally. For example, a method of doing mental arithmetic would be excluded, but a claim for a computer program for a method of performing a calculation would not be excluded (at least, not under the “mental acts” exclusion).

The High Court ruling arose because Halliburton Energy Services Inc appealed against UKIPO’s decision to reject its applications for a method of designing a drill bit using computer simulation.  The method allowed the user to compare simulated performance of different drill designs and so reduce the amount of field testing required.  Significantly, the claims did not include the manufacture of drill bits to the final design.  Had they done so, they would almost certainly have succeeded.  However, Halliburton preferred not to limit its claims in this way in order to maximise the commercial protection for its invention.

The UK Intellectual Property Office has issued a new practice note in light of the judgment stating In future, claims which specify that the invention is implemented using a computer will not be considered to be excluded from patentability as a mental act.”

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