In brief: patent prosecution in Canada

Scope and ownership of patents

Can a patent be obtained to cover any type of invention, including software, business methods and medical procedures?

Pursuant to the Patent Act, patentable subject matter must be an art, process, machine, manufacture or composition of matter or an improvement on one of the foregoing and cannot be a mere scientific principle or abstract theorem.

Methods of medical treatment and surgery are not considered patentable subject matter; however, it is possible, in certain circumstances, for a medical diagnostic method to be patentable. Medical treatment claims framed as uses rather than methods are typically also patentable unless the claims cover subject matter that is considered to impinge upon the skill and judgement of a healthcare professional.

Software and business methods are not per se unpatentable but must overcome subsection 27(8) of the Patent Act in that the claimed subject matter cannot be directed to a mere scientific principle or abstract theorem.

Who owns the patent on an invention made by a company employee, an independent contractor, multiple inventors or a joint venture? How is patent ownership officially recorded and transferred?

In the employment context, in the absence of a written agreement, determination of ownership of patents can be complex. A court may consider many factors in determining whether patent rights belong to an employer, including whether:

• the employee was hired for the express purpose of inventing;
• the employee at the time of hiring had previously made inventions;
• the employer had incentive plans encouraging product development;
• the conduct of the employee once the invention was created suggested ownership was held by the employer;
• the invention was the product of the problem the employee was instructed to solve;
• the employee’s invention arose following his or her consultation through normal company channels (ie, whether help was sought);
• the employee was dealing with highly confidential information or confidential work; and
• it was a term of the employee’s employment that he or she could not use the ideas that he or she developed to his or her own advantage.

A contractor is presumed to own his or her inventions unless an agreement states otherwise.

Where two or more individuals contribute to making an invention, an application for a patent must be made and granted to the inventors jointly; however, if one of them refuses to make an application for a patent or if an inventor’s whereabouts cannot be ascertained after diligent enquiry, the other inventors or their legal representatives may apply for a patent to be granted in the name of the inventors who make the application.

Patents and applications, as well as rights in patents and applications, are transferable in whole or in part. Although it is not mandatory for applicants or patentees to record a transfer or a change of name with the patent office, it is recommended, particularly prior to the commencement of litigation.

Patent office proceedings

How long does it typically take, and how much does it typically cost, to obtain a patent?

The time to obtain a patent in Canada varies depending on complexity and subject area. According to the latest available statistics from the Canadian Intellectual Property Office, the average application takes approximately 31 months (under three years) between a request for examination and granting it.

The cost of preparing a patent application also depends on complexity and subject matter. Typical costs range between C$3,000 and C$15,000 for drafting and filing a patent application.

The cost to prosecute an application through to allowance depends on the number and nature of office actions, including whether and how many prior art references are cited, typically in the range of C$2,000 to C$5,000 per office action response, plus annual maintenance fees and applicable government fees for issuance.

As of 3 October 2022, applicants who request an examination in Canada must also pay an excess claim fee of C$100 for each claim (whether independent or dependent) beyond 20 claims. Depending on the nature of the invention, these fees may be a material factor in consideration of total patent costs.

Are there any procedures to expedite patent prosecution?

The Canadian patent office offers three options to expedite patent prosecution: special order for advanced patent examination, Patent Prosecution Highway (PPH) and applications relating to environmental technology.

A special order for advanced patent examination may be obtained after the laid-open date of the application by paying a prescribed fee and filing a written request for expedited examination, including a declaration that failure to advance the application out of routine order will prejudice the applicant’s rights or a third party’s rights. The application is returned to regular order for examination if the applicant seeks an extension of time for any step during prosecution or if the application is abandoned.

Canada also participates in the PPH for accelerated examination. If a corresponding foreign patent application has been allowed by one of Canada’s designated PPH partner countries, the Canadian application is eligible for PPH. The applicant may submit a request together with the relevant PPH forms after the application is laid open but before substantive examination has begun in Canada.

An applicant may also seek examination out of routine order by filing a declaration indicating that the application ‘relates to technology the commercialization of which would help to resolve or mitigate environmental impacts or to conserve the natural environment and resources’. Examination under this procedure will also be reverted to the routine order if the applicant seeks any extensions of time during prosecution.

What must be disclosed or described about the invention in a patent application? Are there any particular guidelines that should be followed or pitfalls to avoid in deciding what to include in the application?

A patent specification must correctly and fully disclose the invention and how it works. The disclosure must be sufficiently clear and precise to enable a person of ordinary skill in the art to put the invention into practice without any undue burden. For example, in the case of processes of manufacture, each step should be specified, including any steps that distinguish the process from the prior art. In the case of a machine, the principle of operation must be disclosed, and the best mode contemplated by the inventor must be stated.

Although the ‘best mode’ requirement is only expressly specified for the case of machines in the Patent Act, it is recommended that applicants disclose any best or preferred embodiments even for other types of inventions.

In a pharmaceutical case, the Supreme Court of Canada suggested that deliberately filing multiple claims to single compounds within a larger genus, without disclosing which of the individually claimed compounds was contemplated to work the best, can constitute insufficient disclosure that renders a patent invalid.

While there is no specific requirement to disclose experimental data, any data necessary or intended to be relied upon by the applicant should be included in the specification. Where the validity of claims relies on a sound prediction of utility, the courts have, in some cases, required the patentee to disclose both the data to be relied upon for the prediction and the line of reasoning to arrive at the predicted utility.

Must an inventor disclose prior art to the patent office examiner?

There is no explicit requirement to disclose all known prior art to the patent examiner; however, all applicants owe a duty of good faith to the patent office.

The Federal Court has suggested that all material facts must be fairly and fully disclosed to the patent office under this duty of good faith.

Where an applicant is referring to a foreign equivalent patent during examination, it may be required to disclose any prior art and related findings to the patent office. The patent office may also requisition the applicant to provide a list of prior art cited in any related foreign patent application.

May a patent applicant file one or more later applications to pursue additional claims to an invention disclosed in its earlier-filed application? If so, what are the applicable requirements or limitations?

A patent applicant may file a divisional application to pursue additional or revised claims relating to an invention disclosed in an earlier application. A divisional application must be filed before the issuance of the original patent application or before the date of abandonment of the original application. A divisional application should only be filed if the original application is deemed to contain claims pertaining to more than one invention, as it is contemplated that a patent should only be granted for one invention. 

While voluntary divisional applications are procedurally permitted in Canada, they should be cautiously pursued owing to the risk of invalidity from double patenting. In general, a patent applicant who faces a lack of unity or a restriction requirement during prosecution may be permitted to file a later divisional and use the examiner’s objection as a defence to double patenting. Recent decisions have suggested that this may not be an absolute defence depending on the nature of the claims added after the divisional application is filed. 

There is no ability to file a continuation or a continuation-in-part application with a later filing date than the original application.

Is it possible to appeal an adverse decision by the patent office in a court of law?

A decision of the Commissioner of Patents to refuse to grant a patent is appealable to the Federal Court within six months of the final notice of refusal (typically issued following a review by the Patent Appeal Board, which is an advisory body within the Canadian patent office). In general, only final decisions are appealable to the court.

Does the patent office provide any mechanism for opposing the grant of a patent?

Any member of the public can submit a protest in the form of written submissions, including prior art, prior to the grant of a patent. The examiner will acknowledge receipt of the protest and consider the submissions during the examination.

Other than acknowledgement of receipt, the protestor does not receive any substantive or procedural rights from participation. The protestor does not have a direct right of reply to either the applicant or the patent office. Nonetheless, the protestor may monitor the publicly available patent prosecution history and is not prohibited from making multiple submissions before the grant.

Does the patent office provide any mechanism for resolving priority disputes between different applicants for the same invention? What factors determine who has priority?

No, there is no specific mechanism relating to priority disputes. In general, since 1 October 1989, Canada has been a first-to-file jurisdiction, where the first party to file an application is entitled to priority over other parties.

Does the patent office provide procedures for modifying, re-examining or revoking a patent? May a court amend the patent claims during a lawsuit?

The Canadian Patent Office offers several procedures to modify a patent after issuance.

First, if there is an obvious error in a patent that was made by the patent office (including specifications and drawings), the patent office may correct the error either on its own accord or at the request of the patentee within 12 months of issuance. An error is considered obvious if it is obvious in the documents on file that something else was intended and that nothing else could have been intended.

Second, a patentee can apply to reissue a patent within four years of the issue date if the issued patent was defective or inoperative by reason of insufficient description and specification, or by claiming more or less than the patentee had a right to claim, as long as the errors arose from inadvertence, accident or mistake without any fraudulent or deceptive intention. A reissued patent takes the place of the former patent (which must be surrendered).

Third, any person, including the patentee or a third party, can request re-examination by filing prior art and submissions regarding how the prior art applies to the claims. Claims may be amended by the patentee during re-examination, but no proposed amendment may enlarge the scope of an existing claim. There is no time limit to commencing re-examination. A patent can be revoked during re-examination if the patent office determines that the prior art invalidates all claims.

A patentee may also unilaterally disclaim one or more claims or claim elements without formal examination by filing a disclaimer to renounce the claimed subject matter; however, no disclaimer can extend the scope of any claim. A patent may also be dedicated in whole or in part to the public.

The court cannot amend the claims of a patent during a lawsuit. A patentee can choose which claims within a patent to assert (including dependent claims) but cannot redraft the claims via litigation.

How is the duration of patent protection determined?

Canadian patents are in force for 20 years from the deemed filing date of the application, subject to extensions noted below. The filing date is the international (Patent Cooperation Treaty) filing date if the application is a national phase entry originating from an international application, or the Canadian national filing date if the application is a domestic filing.

For pharmaceutical patents, certificates of supplementary protection (CSP) may be available to extend the term of certain patent rights (including infringement) for up to two years to compensate for time spent in research and development and in obtaining marketing authorisation.

A new patent term adjustment (PTA) system will come into force in Canada no later than 1 January 2025. Under this new system, the applicant may apply for an additional term for a patent if the patent is issued after the later of the fifth anniversary of the filing date (or in the case of a divisional or PCT application, the prescribed date – most often the filing date of the parent application), or the third anniversary of the date on which the applicant requested examination. 

The adjusted term is not automatic: the patentee must apply for the extension and pay the prescribed fee within three months after the patent’s issue date.

Periods of delay that are not attributable to the patent office, or are attributable to the applicant, may be deducted from any calculated period. The precise mechanism and factors to be accounted for will likely be announced by regulation in 2024. Under the new system, CSP and PTA terms will run concurrently, both commencing from the patent’s original expiry date.