An invention must be “new” in order to be patentable: Patent Act, s. 28.2. Inventions that are not new are said to be “anticipated”.

Section 28.2 of the Patent Act¹ provides the requirement that the claimed subject matter of a patent must not have been previously disclosed (albeit in a somewhat technical and verbose manner):

28.2 (1) The subject-matter defined by a claim in an application for a patent in Canada (the “pending application”) must not have been disclosed

(a) more than one year before the filing date by the applicant, or by a person who obtained knowledge, directly or indirectly, from the applicant, in such a manner that the subject-matter became available to the public in Canada or elsewhere;

(b) before the claim date by a person not mentioned in paragraph (a) in such a manner that the subject-matter became available to the public in Canada or elsewhere;

(c) in an application for a patent that is filed in Canada by a person other than the applicant, and has a filing date that is before the claim date; or

(d) in an application (the “co-pending application”) for a patent that is filed in Canada by a person other than the applicant and has a filing date that is on or after the claim date if

(i) the co-pending application is filed by

(A) a person who has, or whose agent, legal representative or predecessor in title has, previously regularly filed in or for Canada an application for a patent disclosing the subject-matter defined by the claim, or

(B) a person who is entitled to protection under the terms of any treaty or convention relating to patents to which Canada is a party and who has, or whose agent, legal representative or predecessor in title has, previously regularly filed in or for any other country that by treaty, convention or law affords similar protection to citizens of Canada an application for a patent disclosing the subject-matter defined by the claim,

(ii) the filing date of the previously regularly filed application is before the claim date of the pending application,

(iii) the filing date of the co-pending application is within twelve months after the filing date of the previously regularly filed application, and

(iv) the applicant has, in respect of the co-pending application, made a request for priority on the basis of the previously regularly filed application.

There is a two part test for anticipation, which is a question of fact. The Supreme Court in Apotex Inc v Sanofi-Synthelabo Canada (Plavix)² set out the following two elements to determine whether a piece of prior art (meaning anything published before the filing date of the patent) anticipates a claimed invention:³

1. it must disclose the invention of the patent in question; and
2. it must enable a skilled reader to make the invention, taking into account common general knowledge and allowing for some non-inventive trial and error.

This two-step approach is a refinement of previous jurisprudence on anticipation, a classical statement of which is found in Beloit Canada v Valmet Oy:⁴

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 the possibility of error be led to the claimed invention.

Anticipation must be found in a specific patent or published document, and not bits and pieces from a variety of prior publications melded together. Courts are wary of hindsight analysis, thus, “[a]nticipation by publication is a difficult defence to establish because courts recognize that it is all too easy after an invention has been disclosed to find its antecedents in bits and pieces of earlier learning. It takes little ingenuity to assemble a dossier of prior art with the benefit of 20-20 hindsight.”⁵

Any document can be considered prior art, so long as it is available to the public. “[B]eing available does not require that access to the information be easy, simply that it be possible using known methods and instruments.”⁶ If a book is available in a public library, even if the book is in a different language, and even if one could prove that nobody had ever accessed the book, it would still count as public disclosure.⁷

For prior art to anticipate an impugned patent, a skilled person “must […] be able to perform or make the invention of the […] patent without undue burden.”⁸

Rothstein J. set out a summary of the jurisprudence relating to enablement in Plavix, and stated the following four non-exhaustive factors to be considered:⁹

1. 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.
2. 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.
3. 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.
4. 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.

Public use or sale of an invention, whether as a standalone product or as part of a product, can constitute anticipating public disclosure so long as such a use or sale would enable a member of the public to make or obtain the invention. In Baker Petrolite v Canwell Enviro-Industries,¹⁰ Rothstein J.A. (as he then was) laid down a test for determining when a public sale or use constitutes anticipating disclosure:¹¹

1. 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 paragraph 28.2(1)(a). The disclosure must make the necessary invention available.
2. For a prior sale or use to anticipate an invention, it must amount to “enabling disclosure” so as to make available information as to its contents and its methods of manufacture or to be enabled to make or obtain the invention.
3. 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 because direct and unambiguous access to information concerning the composition or internal structure of a prior used product is possible.
4. 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 to find the invention without the use of inventive skill
5. When reverse engineering is necessary and capable of discovering the invention, an invention becomes available to the public if a product containing the invention is sold to any member of the public who is free to use it as she or he pleases. Communicating the invention to a single member of the public without inhibiting fetter is enough to amount to a making available to the public. The grant of a patent depends on the inventor giving to the public something it did not have before. If the public already has it, then the inventor gives nothing and is not entitled to anything in return, i.e. a monopoly for a period of years.
6. It is not necessary to demonstrate that a member of the public actually analysed the product that was sold in the case or prior use nor read the book or whether it was situated in a dark and dusty corner of the library.
7. 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, in this respect, is only whether inventive skill was required.
8. 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 (the invention) that must be disclosed through the analysis. Novelty of the claimed invention is destroyed if there is disclosure of an embodiment which falls within the claim. A complete analysis of a prior used product so as to enable an exact reproduction of such product is not necessary in order to destroy the novelty of the claimed product.