Will the Real Person Skilled in the Art Please Stand Up?


In determining whether an invention can be patented in Canada, one of the requirements is that the invention must not be obvious. Obviousness can be a significant hurdle in acquiring a patent and the law on this doctrine can be challenging to figure out. Essentially, the non-obvious requirement means there must be some level of inventiveness to the subject matter of the patent. The “man skilled in the art” is the hypothetical person used for determining obviousness i.e. would the invented subject matter have been obvious to the person skilled in the art or would there be some degree of invention required for this person to arrive at the invented item. If obvious, a patent application will not be successful.

The most important element in attacks on patents on the issue of obviousness is the definition of this man skilled in the art. The most enduring definition is the following from the case of Beloit Canada Ltd. v Valmet Oy1:

…the technician skilled in the art but having no scintilla of inventiveness or imagination; a paragon of deduction and dexterity, wholly devoid of intuition; a triumph of the left hemisphere over the right. … the man in the Clapham omnibus of patent law…

He also goes by the person having ordinary skill in the art, the person of ordinary skill in the art, the skilled addressee, person skilled in the art or simply the skilled person. For someone who goes by so many names, it is hard to understand how he does not exist, even less how he can be so important to a patent litigation case without ever showing up in court.

Who Is This Person and Why Is He/She So Important?

The “starting point” of the approach to an obviousness attack on a patent has always been one of consideration of the common general knowledge of the person skilled in the art (the “PSIA”). More and more, courts view the concept of the person skilled in the art as more of an entire team of persons skilled in the art. Now, in all fairness that seems to make sense, except that for a patentee, it unfortunately creates a higher threshold of inventiveness than before.

The argument for a team of persons skilled in the art stems largely from the complexity of the inventions developed in recent years. Pharmacological discoveries in particular seem subject to this trend and arguably, unnecessarily so. For example, looking at the invention of clopidogrel bisulfate2, the Applicant argued that the person skilled in the art was a formulation chemist with experience in stereochemistry, chiral separation and drug discovery. One questions how a Court could argue otherwise? In fact, the Court considered that there was more to the understanding of the patent in question than possessing merely the skill of pharmaceutical chemistry, concluding that the PSIA had to be approached as a team of skilled persons “holding a PhD in pharmaceutical chemistry; with several years of experience working in the fields of pharmacology and toxicology; and having good general knowledge of haematology and medicine”3.

It can be argued that it is not necessary for the PSIA to encompass the breadth of possible knowledge dealt with in a patent. This team approach in fact seems counterintuitive as the distinguishing feature between the invention of the patent in this case and the closest prior art was the fact that it consisted of the isolation of the two isomers from a known racemic mixture and the preparation of pharmaceutical salts. At best, the testing was routine, the steps to isolate the isomers were the invention.

The majority of “pharmacological salt or racemate” patents court cases arguably suffer from a similar lapse in logic where courts defined the PSIA as a team of individuals of various experiences/education levels.4

What If the Qualifications of the PSIA are Stretched Too Far?

The importance of the qualifications lies in the fact that when assessing obviousness in court, the experts may unwittingly create a team more akin to inventors than simple technicians. The mythical person will be “given” knowledge and skills that possibly nobody really has, thereby creating an undesirable hybridized creature replete with knowledge and experience beyond what was needed for the exercise of assessing the validity of patent claims. The danger is that the more knowledgeable the PSIA, the easier it is to succeed in establishing the invention was obvious and therefore unworthy of patent protection. This becomes even easier when using a team of skilled individuals parading as the PSIA. The leap to obviousness for the PSIA depends on the latter’s common general knowledge. The more experienced and knowledgeable and the more people involved, the easier the leap; the reverse is also true.

A prime example of the importance of defining the person skilled in the art can be found in the recent decision of Novartis Pharmaceuticals Canada Inc. v Teva Canada Ltd.5 On the one hand, TEVA, challenging the patent on the basis of obviousness, argued that the person skilled in the art should be comprised of a team of individuals “made up of a chemist, a physician familiar with iron overload conditions, and a person knowledgeable about pharmacological testing of iron chelators”.6 On the other hand, Novartis argued that the skilled person is “a medicinal chemist with knowledge of iron overload conditions”.7 Ultimately, the Court sided with Novartis and the allegation of obviousness failed.

This is not to say that the obviousness attacks against patent claims are only determined by the selection of the PSIA, but as the first step in the determination one should be wary of how he or she tries to define this mythical creature. The importance of identifying the PSIA starts as early as the time of defining the patented invention and drafting the patent application and this is reflected in the comments of the Court in Janssen-Ortho Inc. v. Novopharm Ltd.8 (“Janssen-Ortho”) wherein it was stated “The ordinary person skilled in the art in this case can be ascertained from the language of the specification of the Patent”. Accordingly, it is important to note that the exercise starts at the drafting stage — in the determination and description of the problem to be solved.

Impact Beyond Pharmaceutical Patents

In Newco Tank Corp. v Canada (Attorney General)9 in an appeal from the Re-Examination Board, one of the main issues was whether the Board had reasonably defined the skill of the PSIA. The Court recalled Janssen-Ortho,10 where the exercise was adequately summed up as follows:

…Care must be taken in describing a person skilled in the art as there could be danger in defining such a person so narrowly that few, if any, would qualify. Conversely, if the net is cast too broadly, a danger exists in bringing in those unfamiliar with the field. The Court must take a fair and generous view as to what sort of person comprises a person skilled in the art. That person is the ordinary person skilled in the art, not the least qualified or slowest witted. It must not be too astute or technical in its inclusion or exclusion of any group of persons…

The interesting aspect in this case relates to the battle over the breadth of knowledge of the PSIA. Newco argued that the Board had improperly defined the PSIA as a technician skilled in the art of oil production which field was then broadened to include “oil field operations”, and then broadened again to include “the fields of hot water tanks and water wash systems for cars”. Newco argued that no skilled person could have the required knowledge of all of the components of oil production, let alone oil field operations and hot water tank systems and as a result the PSIA as defined by the Board resembled more an engineer than a technician. The Court found that the Board had applied the correct test in determining the fictional person skilled in the art.

In Bauer Hockey Corp. v Easton Sports Canada Inc.11 the Court struggled with the identification of the PSIA in a patent challenge relating to skate boots. Some experts testifying in the case had no experience in the field. The Court noted:

Normally, it should not be difficult to define the person ordinarily skilled in the art, to whom a patent is addressed. In this case, this became the subject of much debate, particularly because Mr. Tonkel, who commented on the construction and the invalidity of the patent, had no experience whatsoever in designing or manufacturing skates.12

Given the complexity of the subject matter and the lack of consensus as to who could be a PSIA, the Court reiterated the importance of properly defining the PSIA and resorted to fabricating a team of individuals to represent the PSIA as follows:

Considering the evidence as a whole, I have come to the conclusion that the person to whom the ‘953 Patent is addressed is in fact a team or the following individuals working within a team:

  • An industrial designer with at least one year of experience in footwear or hockey skates who works as part of a skate design/development team; or
  • An experienced footwear or a skate designer or developer who works within such a team; or
  • An experienced skate pattern maker or an experienced footwear pattern maker working with people who have experience in the conception or manufacturing of skates.13

Following a lengthy analysis of the invention, the person skilled in the art, commercial considerations regarding the commercial adoption of the design and the motivation to find solutions to known problems with the available skates, the Court found the invention non-obvious.


Depending on the technological field of the invention, the PSIA can be a complex construct defined by the technology, the prior art, common general knowledge and a balance between education and work experience. As such, the many facets of the PSIA need to be considered at the time of drafting the application as the background of the invention helps shape the eventual definition of the PSIA, whether during the prosecution or future litigation.


1 (1986) 8 C.P.R. (3d) 289 (F.C.A.) at 293.

2 Apotex Inc. v. Sanofi-Aventis, 2011 FC 1486 [Apotex] overturned on other grounds at 2013 FCA 186

3 Apotex at para 649.

4 See Ratiopharm Inc. v. Pfizer Ltd. 2009 FC 711, Astra Zeneca Canada Inc. v. Apotex Inc. 2014 FC 638 and Lundbeck Canada Inc. v. Canada (Minister of Health) 2009 FC 146.

5 2015 FC 770 [Teva].

6 Teva at para 20.

7 Teva at para 20.

8 2006 FC 1234. [Janssen-Ortho]

9 2014 FC 287.

10 Janssen-Ortho at para 90.

11 2010 FC 361. [Bauer Hockey]

12 Bauer Hockey at para 112.

13 Bauer Hockey at para 122.