For a patent to be valid in Canada, the invention claimed therein needs to be new and inventive. In patent law, these requirements are known as novelty and non-obviousness. A patent cannot in theory be granted for an invention without meeting these basic requirements or at least, if a patent which does not meet these requirements is granted, it cannot later be maintained. These requirements are borne out of a combination of statute and case law.

Novelty

The definition of “invention” in section 2 of the Patent Act (R.S.C., 1985, c. P-4)Patent Act, RSC 1985, c P-4. uses the word “new”. This means the invention must not already be known. Section 28.2(1) of the Patent Act explicitly codifies the novelty requirement.Patent Act, RSC 1985, c P-4, s. 28.2(1).

Section 28.2 thus blocks patent applications if the applicant, or someone who obtained their knowledge from the applicant, made the invention public more than a year before applying; if anyone else made the invention public before the application; or if the invention is already subject to an earlier patent application.

Disclosure by the applicant

Paragraph 28.2(1)(a) provides a grace period that allows claims to "subject matter" in a patent (application) in Canada up until twelve months after its public disclosure by the applicant or somebody who obtained knowledge about it from the applicant.Patent Act, RSC 1985, c P-4, s. 28.2(1). It can also allow inventors to discuss their invention with potential investors, for instance, without requiring non-disclosure agreements. However, since such a grace period is non-universal, it remains limited in its helpfulness to inventors.David Vaver, Intellectual Property Law: Copyright Patents Trade-Marks, 2d ed (Toronto: Irwin Law Inc., 2011) at 320.

Disclosure by another party The section also provides that the subject-matter defined in the claim cannot have been previously disclosed in Canada or elsewhere.Patent Act, RSC 1985, c P-4, s. 28.2(1)(a) and (b). If the subject-matter has been disclosed in Canada or in a foreign jurisdiction, a patent cannot be granted on the same subject-matter in Canada.

The section does not restrict disclosure to prior patents. As long as the subject-matter was disclosed “in such manner that the subject-matter became available to the public”, the subject-matter is barred from being patented.Patent Act, RSC 1985, c P-4, s. 28.2(1)(a) and (b). This includes prior patents, publications, or the invention itself being put on display. Disclosures in a private document, such as an internal memo that is not available to the public, do not count.David Vaver, Intellectual Property Law: Copyright Patents Trade-Marks, 2d ed (Toronto: Irwin Law Inc., 2011) at 321. Ignorance regarding prior disclosure is not an excuse.

Where there has been prior disclosure of the same subject-matter, the invention will be deemed to be not novel, the prior disclosure being anticipatory of the invention. However, the prior disclosure must be sufficiently detailed to be anticipatory. The disclosure must also be self-contained; a combination of prior art is not adequate for showing anticipation.

In Reeves Brothers Inc. v. Toronto Quilting & Embroidery Ltd.,Reeves Brothers Inc. v. Toronto Quilting & Embroidery Ltd. (1978), 43 C.P.R. (2d) 145 at 187 (FCTD). Justice Gibson the Federal Court enunciated an eight-pronged test for determining whether prior art is anticipatory of the subject-matter of a patent. The prior art must:

give an exact prior description; give directions which will inevitably result in something within the claims; give clear and unmistakable directions; give information which for the purpose of practical utility is equal to that given by the subject patent; convey information so that a person grappling with the same problem must be able to say "that gives me what I wish"; give information to a person of ordinary knowledge so that he must at once perceive the invention; in the absence of explicit directions, teach an "inevitable result" which "can only be proved by experiments"; and satisfy all these tests in a single document without making a mosaic.

The final statement is credited with creating a misinterpretation that the tests are cumulative. However, the tests are not cumulative. The Court of Appeal has commented that "Gibson J. had only enumerated various formulations for the test of anticipation retained in earlier decisions and his conclusion really is that there could be no finding of anticipation unless one met any, rather that each of these eight 'tests'.Diversified Products Corp. v. Tye-Sil Corp. (1991), 35 C.P.R. (3d) 350 at 361 (FCA)

In Beloit Canada Ltd. et al v. Valmet Oy, one of the leading cases on anticipation by publication, the Federal Court of Appeal stated:

One must, in effect, be able to look at a prior, single publication and find in it all the information which, for practical purposes, is needed to produce the claimed invention without the exercise of any inventive skill. The prior publication must contain so clear a direction that a skilled person reading and following it would in every case and without possibility of error be led to the claimed invention.Beloit Canada Lt. et al. v. Valmet Oy (1986), 8 CPR (3d) 289 (FCA).

In Baker Petrolite Corp. v. Canwell Enviro-Industries Ltd.,Baker Petrolite Corp. v. Canwell Enviro-Industries Ltd. (2002), 17 C.P.R. (4th) 478 (FCA). the Federal Court of Appeal listed the following eight principles for anticipation by prior use or sale, which supplement the principles from Beloit Canada Ltd. et al v. Valmet Oy:

Sale to the public or use by the public alone is insufficient to prove anticipation. Disclosure of the invention is required to constitute anticipation under section 28.2(1)(a) of the Patent Act. For a prior sale or use to anticipate an invention, it must amount to “enabling disclosure”. The prior sale or use of a chemical product will constitute enabling disclosure to the public if its composition can be discovered through analysis of the product. The analysis must be able to be performed by a person skilled in the art in accordance with known analytical techniques available at the relevant time and without the exercise of inventive skill. When reverse engineering is capable of discovering the invention, it becomes available to the public if a product containing the invention is sold to any one member of the public who is free to use it as she or he pleases. It is not necessary to demonstrate that a member of the public actually analyzed the product sold. The amount of time and work involved in conducting the analysis is not determinative of whether a skilled person could discover the invention. The relevant consideration is only whether inventive skill is required. It is not necessary that the product that is the subject of the analysis be capable of exact reproduction. It is the subject matter of the patent claims that must be disclosed through the analysis. Novelty of the claimed invention is destroyed if there is a disclosure of an embodiment which falls within the claim.

In Apotex Inc. v. Sanofi‑Synthelabo Canada Inc., it was claimed that Sanofi-Synthelabo’s patent was invalid because it covered only a selection of a prior, broader genus patent. One of the alleged grounds of invalidity was lack of novelty. The Supreme Court of Canada employed a two-part test for anticipation. In order for there to be a finding of anticipation, the prior art must satisfy both of the following branches: prior disclosure; and enablement.

The test for disclosure is whether a person skilled in the art, reading the prior patent, would understand that it discloses the special advantages of the second invention. No trial and error is permitted.

Once it is established that the prior disclosure indicates the special advantages of the second invention, some trial and error or experimentation is permitted to determine whether that disclosure also enables the development of the second invention. However, the skilled person must be able to perform or make the invention of the second patent without undue burden.

The Supreme Court based their test on an earlier British test: “Patents are meant to teach people how to do things. If what is “taught” involves just too much [work] to be reasonable allowing for all the circumstances including the nature of the art, then the patent cannot be regarded as an “enabling disclosure.” . . . The setting of a gigantic project, even if merely routine, will not do."Halliburton Energy Services Inc. v. Smith International (North Sea) Ltd., EWCA Civ 1715 (BAILII).

The prior art information must thus: be clearly disclosed, and enable the skilled worker to make or perform the invention.Apotex Inc. v. Sanofi‑Synthelabo Canada Inc.

The Supreme Court stated four non-exhaustive factors to be considered in determining whether there has been enablement:

Enablement is to be assessed having regard to the prior patent as a whole including the specification and the claims. There is no reason to limit what the skilled person may consider in the prior patent in order to discover how to perform or make the invention of the subsequent patent. The entire prior patent constitutes prior art. The skilled person may use his or her common general knowledge to supplement information contained in the prior patent. Common general knowledge means knowledge generally known by persons skilled in the relevant art at the relevant time. The prior patent must provide enough information to allow the subsequently claimed invention to be performed without undue burden. When considering whether there is undue burden, the nature of the invention must be taken into account. For example, if the invention takes place in a field of technology in which trials and experiments are generally carried out, the threshold for undue burden will tend to be higher than in circumstances in which less effort is normal. If inventive steps are required, the prior art will not be considered as enabling. However, routine trials are acceptable and would not be considered undue burden. But experiments or trials and errors are not to be prolonged even in fields of technology in which trials and experiments are generally carried out. No time limits on exercises of energy can be laid down; however, prolonged or arduous trial and error would not be considered routine. Obvious errors or omissions in the prior patent will not prevent enablement if reasonable skill and knowledge in the art could readily correct the error or find what was omitted.

As an example of an application of this test: under the disclosure branch of the test, a compound is not clearly disclosed simply because it is part of a larger class of compounds; under the enablement branch, a compound is not enabled simply by disclosing its theoretical formula, unless the compound has actually been prepared or the skilled worker would know, from the given directions or his ordinary knowledge, how to prepare it.David Vaver, Intellectual Property Law: Copyright Patents Trade-Marks, 2d ed (Toronto: Irwin Law Inc., 2011) at 323.

Earlier patent application Priority is determined by order of applications, thus a prior application will bar a subsequent one.Patent Act, RSC 1985, c P-4, s. 28.2(1)(c). This "first to file" approach is used globally. Although previously holding to its "first to invent" system, the United States, switched on March 16, 2013, after the enactment of the America Invents Act (see "First to file and first to invent"). An earlier application that remains secret because it is abandoned or withdrawn before being published does not constitute disclosure.David Vaver, Intellectual Property Law: Copyright Patents Trade-Marks, 2d ed (Toronto: Irwin Law Inc., 2011) at 320.

Non-obviousness