CIPO Issues New Guidance on Patentability of Computer-Implemented Inventions

On March 8, 2013, the Canadian Intellectual Property Office (CIPO) published its practice guidance following the Federal Court of Appeal decision in Canada (Attorney General) v. This practice notice, "Examination Practice Respecting Computer-Implemented Inventions,"1 attempts to clarify CIPO’s position regarding its evaluation of computer-implemented inventions as patentable subject matter under the Patent Act. The notice, which follows public consultation from the spring of 2012,  specifically rescinds examination guidance from 2011 that CIPO examiners have been applying.

Computer as an Essential Element

The notice sets out the CIPO position that if a patent claim recites a computer that is an essential element of a construed claim, CIPO will generally conclude that patentable subject matter has been claimed. The notice provides that purposive construction should be applied to determine whether a claimed computer is an essential element. The practice notice suggests that if a computer is only a convenience or an afterthought, the CIPO examiner may conclude that the computer was not an essential element.

The notice gives the example of a computer that only performs calculations that can be achieved by pen and paper or mentally, which under the notice would be classified as a non-essential feature. In this respect, the examination procedure set out in the notice for determining whether a computer is an essential element appears to describe only a subset of the tests for purposive construction as set by the Supreme Court in Free World Trust v. Électro-Santé Inc. and Whirlpool Corp. v. Camco Inc. For instance, the CIPO notice does not refer to any evaluation of the intent of the inventor, as expressed in the patent application and as governing the essential element analysis.

The notice goes on to state that if a claimed computer cannot be varied or substituted without making a difference in the way the invention works or that if the computer is required to resolve a practical problem, the computer may be considered an essential element. This latter statement seems to be at odds with the earlier example in the notice of a computer being non-essential if it only offers a convenience: since every computing operation can be simplified to a series of binary operations that can be performed manually, albeit very slowly and inefficiently, it seems only logical that the addition of a computer would in most cases be a solution to the practical problems of speed, cost and efficiency.

It remains to be seen how CIPO will take into account the intent of the inventor as expressed in the application, and how CIPO examiners will resolve the question of whether a computer solves a practical problem or is a mere convenience. Further positions and procedures may need to be developed by CIPO in this regard, perhaps through an examination of whether a person of skill would consider the substitution of a computer with manual pen and paper calculations to be practical in determining whether a computer was essential.

Interestingly, the notice is silent on the examination procedure when computers are found to be non-essential elements. This silence may suggest an approach whereby a CIPO examiner will simply declare a computer-implemented invention to be non-patentable once the examiner concludes that a computer is non-essential; or it may imply that the examiner will continue to consider the patentability of the patent claim on the basis of the other elements of the claim that are determined to be essential.

For further details, see Practice Guidance.


1 Issued as Exam Memo PN2013-03. An accompanying Exam Memo PN2013-02 setting forth the office position on purposive construction of patent claims was simultaneously issued by CIPO.



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