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Patenting in Canada vs. the United States

ATMAC Nov 07 2019

Although the Canadian patent regime has many similarities with that of its southern neighbor, it can be helpful to understand where the two countries differ. This white paper explains several key differences and provides tips for persons already familiar with patenting in the United States to maximize effectiveness when filing and prosecuting applications in Canada.

Overview – Key differences between Canadian and US patent systems

  Canada United States
Grace period 1-year from Canadian filing date 1-year from effective filing date
Examination Examination fees only required when requesting examination and can be deferred for 4 years (or 5 years for applications before Oct. 30, 2019) Examination fees required at filing and additional fees required to defer examination
Prosecution with Examiner Unlimited Office actions and amendments if Examiner feels prosecution is being advanced Typically 2nd Office action will be made “final” and then applicant will need to pay RCE fees to continue
Obviousness rejections Can only be based on prior applications that were published and therefore available to the inventor Can be based on any prior application filed in the US regardless of publication date
Continuing applications Divisional applications only Divisional, continuation, and continuation-in-part applications
Claims fees None Extra claims fees required for claims in excess of 20, independent claims in excess of 3, multi dependencies
Reinstatement after abandonment Reinstatement by right is possible within one-year of abandonment for most reasons, a showing of due care is only required for reinstatement due to missed maintenance fees or missed request for examination Reinstatement only possible if the abandonment and delay in requesting reinstatement were unintentional
Maintenance fees Annual maintenance fees required starting on the 2nd anniversary of the filing date Maintenance fees required only for issued patents by 4, 8, and 12 years after patent issue date
PCT national entry deadline

30 months from the earliest priority date for on time entry

42 months from the earliest priority date with the mere payment of an additional $200 CAD late fee for PCT applications with a filing date before Oct. 30, 2019 and with an additional statement that the failure was unintentional for applications with a filing date on or after Oct. 30, 2019

30 months from the earliest priority date
Small entity Fifty (50) employees Five-hundred (500) employees


Grace period – 1 year from Canadian filing date, not priority date

Canadian patent law permits inventors to publicly disclose their invention up to one year prior to filing for a patent in Canada. Any public disclosures by the inventor, or by any other person who obtained knowledge either directly or indirectly from the inventor, cannot be used to reject a Canadian patent application under anticipation or obviousness as long as the public disclosure was within one year of the Canadian application’s filing date. PCT international patent applications are considered to be Canadian applications if the national phase is entered in Canada.

Although a Canadian patent application (or PCT application) may also benefit from a priority claim under the Paris convention back to one or more earlier filed applications in other countries, the grace period protecting against self-disclosure in Canada does not benefit from Paris priority. This differs from the grace period in the United States, which does benefit from Paris priority because the US grace period extends backward one year from the effective filing date of the US application (i.e., the earliest priority date).

Practice tip

To take advantage of the grace period in Canada, make sure to get the Canadian patent application (or the PCT international application) filed within one (1) year of the earliest public disclosure regardless of any additional time the Paris priority period would otherwise allow.


Examination – only upon request

The Canadian Intellectual Property Office (CIPO) will only examine a patent application in Canada in response to a specific request for examination. The examination fee is payable upon request, and the request can be deferred up to four (4) years from the Canadian application’s filing date for applications filed on or after Oct. 30, 2019 and for up to five (5) years for applications filed prior to Oct. 30, 2019. This differs from US practice where US provisional applications only preserve rights for one (1) year, and examination of US non-provisional applications is automatic and the examination fees are due upon filing or national entry into the US.

  • An applicant that desires to quickly obtain an issued patent in Canada should request examination and pay the examination fees at the time of filing or national entry.
  • An applicant that desires to preserve their rights in Canada while minimizing costs may simply file or enter the national stage in Canada without requesting examination.

When deferring examination until later, it is important to understand that patents in Canada expire twenty years after the Canadian filing date so any delay in requesting examination will also delay the beginning of the enforceable period of any patent issued on the application. However, for many applicants, delaying the issuance of the patent is a worthwhile trade-off to keep initial costs low while the applicant works towards getting allowance in the United States and/or other countries. Once allowance is reached in other countries, the Canadian application can be amended to add in the claims that have been allowed in the other countries, and to request and pay for examination.

Practice tip

For applicants that are only planning to file a patent application in the United States, consider also filing a corresponding application in Canada without requesting examination. Very little initial investment is required to preserve patent rights in Canada.

Prosecution with Examiner – unlimited Office actions, typical four (4) months for reply

During the examination phase of a Canadian patent application, the Examiner will mail reports requisitioning the applicant to make amendments and/or arguments to overcome any problems. Unlike in the United States where second Office actions are typically labelled as “final” rejections, final rejections in Canada are rare. Canadian Examiners will continue to send out new reports and permit amendments / arguments to be made at no cost as long as the Examiner feels progress toward allowance is being made. Only in the event of a total impasse or a specific request by the applicant will a final rejection be made by a Canadian Examiner.

In addition to the absence of anything equivalent to a request for continued examination (RCE) and the associated RCE fees, Canadian Office actions will typically set forth a four (4) month period for reply. Extension of time is possible to use the full six month period; however it must be requested before the original four month period for reply expires. This differs from the US where the applicant can miss the shortened 3-month response deadline and then simply pay extension of time fees to make a reply to an Office action at the end of the six-month statutory reply period.

Obviousness rejections – only based on published references

In Canada, Examiners are not permitted to make obviousness rejections based on secret references that were not published at the time of the effective date of the claim under examination. In other words, as long as there is at least one specific difference in the claimed subject matter with the prior art, the Examiner can only allege the difference would have been obvious in view of published applications that were available to the inventor. This differs from US law where an Examiner can base obviousness rejections on so called “secret” prior art references that were confidential and not available to the inventor before the inventor filed the patent application.

Because of these legal differences, any time an obviousness rejection is made in the United States based on references that only qualify as prior art under pre-AIA 35 U.S.C. 102(e) or post-AIA 35 U.S.C. 102(a)(2), it will not be possible for the Canadian Examiner to apply the same rejection in Canada. Combined with the fact that there are not as many patent applications filed in Canada to begin with (meaning less chance of a pure anticipation rejection based on secret prior art, which, like the US, is permissible in Canada), it is often possible to secure patent protection in Canada on claims broader in scope than what the applicant can get allowed in the US.

Practice tip

If an obviousness rejection is made in the United States based on references that only qualify as prior art under pre-AIA 35 U.S.C. 102(e) or post-AIA 35 U.S.C. 102(a)(2), consider presenting the same claims in Canada as they may be allowable without any amendment or argument.

Continuing applications – must be a true “divisional”

There are two types of patent applications in Canada: regular patent applications (which include PCT applications that have entered the national phase in Canada), and divisional applications (which have the same description and figures as their parent application but claim a different invention). Unlike in the United States, there are no continuation or continuation-in-part applications available in Canada.

In the United States, a common prosecution strategy is to accept allowable but non-ideal claims in a first application and then file a continuation application to pursue better claims on the same invention. This strategy will generally not be successful in Canada. The reason is that any claims in a divisional application that are directed to the same invention as the parent application will be rejected with a double patenting rejection. Since there is no terminal disclaimer available in Canada, the only way to overcome such rejection is to cancel the claims directed to the same invention in the divisional application.

Practice Tip

Include all claims supported by the application as early as possible even if some claims may be directed towards different inventions. Any divisional application should be initiated at the request of CIPO (not voluntarily by the applicant), thereby reducing the risk of the divisional patent being invalidated on the grounds of double patenting.

Claims – no excess or multiple dependent fees

A Canadian patent application can have any number of claims. There are no extra fees required and “multiple dependent” claims are permitted even when based on other multiple dependent claims. This differs from the US were extra fees are required for each claim in excess of twenty, for each independent claim in excess of three, and when the claims include multi-dependencies.

Practice Tip

If you have multiple foreign counterpart patent applications, include all claims from the entire family of applications in a single Canadian patent application. If new claims are added in foreign apps over time, consider filing voluntary amendment(s) in Canada to add them in to the Canadian application prior to issuance. This may maximize scope with an extensive combination of broad to narrow claims in the Canadian patent.

Reinstatement after abandonment – within 1 year

If a Canadian patent application is abandoned because of the applicant’s failure to take some action, reinstatement is possible for one (1) year from the date of abandonment. To reinstate the application, the applicant needs to request reinstatement, pay a $200 CAD reinstatement fee, and take whatever action that should have been taken to avoid the abandonment in the first place.

For applications that have a filing date before Oct. 30, 2019, there is no requirement that the abandonment occurred despite due care or was unintentional. However, for applications that have a filing date on or after Oct. 30, 2019, due care must be shown if reinstatement is requested six months after a missed maintenance fee or the deadline for requesting examination. The logic behind this is that the maintenance fee and request for examination deadlines were known the date the application was filed; thus, if they are missed more than six months, there should be a good reason why.

Again, with the caveat for missed maintenance fee and request for examination deadlines for applications filed on or after Oct. 30, 2019, in Canada, it is permitted for an applicant to deliberately let their application go abandoned such as to pause examination while they work to get allowance in another country or to save up money to continue prosecution.

Practice Tip

If a Canadian patent application is rejected for formalities only but you are still making claim amendments in counterpart foreign applications, consider letting the Canadian application temporarily go abandoned. You will then have one (1) year to finalize the claims in the foreign applications and add these new claims in to the Canadian application before reinstatement must be requested.

Maintenance fees – annual, from 2nd anniversary of filing date

Annual maintenance fees are required for all applications and issued patents in Canada starting on the 2nd anniversary of the Canadian filing date. This differs from US practice where maintenance fees are only required for issued patents by the 4th, 8th, and 12th years after the patent issue date.

Any person authorized by the applicant or patentee may pay maintenance fees in Canada.

Practice Tip

If you would like your patent agent to handle maintenance fees but you would like to save service fees on maintenance fees, consider asking your patent agent to pay multiple years worth of maintenance fees in a single submission. The online maintenance fee payment system allows any number of years’ worth of fees to be paid in advance in a single submission. For example, paying the maintenance fees in five year blocks would require only four submissions rather than eighteen thereby significantly reducing patent agent service fees.

Late PCT national entry – 42 months from priority

Although, the on-time PCT national entry deadline for Canada is thirty (30) months from the earliest priority date, for PCT applications with a filing date before Oct. 30, 2019, late entry can be done up to 42 months from the earliest priority date by the mere payment of an additional $200 CAD late fee. This nominal fee is all that is required for late entry and the applicant does not need to provide any reason or explanation of why the national entry was late. For PCT applications filed before Oct. 30, 2019, it is perfectly acceptable to delay national entry in Canada to the full 42 months simply to defer the national entry costs or to wait for allowance in one or more other countries.

For PCT applications filed on or after Oct. 30, 2019, late PCT national entry is still possible up to 42 months from the earliest priority; however, a statement must be made that the failure to file on time was unintentional.

Once the 42-month deadline has passed, however, it is no longer possible to enter the national phase in Canada. There is no provision available to further extend this deadline past 42 months from the earliest priority so do not miss this deadline or patent rights will be lost.

Small entity discounts – for companies up to 50 employees

Many of the government fees charged by CIPO are reduced by one half for applicants that qualify as a small entity. In Canada, the small entity requirements require the applicant to be an entity that employs fifty (50) or fewer employees or that is a university. This differs from small entity in the United States where the limit is five-hundred (500) employees or a university.

Furthermore, small entity status in Canada is determined only once – at the time the Canadian patent regime is engaged. This will either be on the filing date for an application filed directly with CIPO, or on the national entry date for a PCT application entering the national phase in Canada. Once small entity status is properly established by submitting a signed small entity declaration, the application and any patent issued therefrom remains entitled to small entity discounts for its entire life regardless of any changes in entity size of the original applicant or assignments to new owners. This differs from United States practice where small and micro entity status must be repeatedly reviewed during the life cycle of each application/patent so that changes in entity status can be reported to the USPTO and future fees can be paid at the new entity level.

Other differences between Canadian and US patent regimes

The above-described differences are not the only ways the Canadian and US patent systems differ from one another. Other differences include:

  • No IDS / duty of disclosure obligations in Canada, the applicant only needs to submit documents specifically requisitioned by the Canadian Examiner (unlike in the US where all known references material to patentability must be reported)
  • Accelerated examination available in Canada to applicants for a nominal fee of $500 CAD for any entity size (unlike in the US where Track-1 prioritized examination costs $4000 USD, $2000 USD, or $1000 USD for large, small, and micro entities, respectively)
  • Free accelerated examination available in Canada if the applicant simply files 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 (unlike in the US where a complicated accelerated examination (AE) petition must be filed to benefit from accelerated examination for environmental quality inventions)
  • Only registered “Patent Agents” who have passed to the agent exams can represent others before the Canadian Intellectual Property Office (CIPO); in Canada any lawyer could refer to themselves as a “Patent Attorney” or “Patent Lawyer” even if they have not passed the agent exams and are not licensed to represent applicants before CIPO (unlike in the US where there are official designations of “Patent Attorney” and “Patent Agent” before the USPTO depending on whether the person who passed the patent bar is also an attorney)

Blueprint for success

Not only do Canadian patent applications have lower cost and a more flexible application process than corresponding US applications, Canadian applications generally have an easier time reaching allowance than their US counterparts. These facts can be leveraged by companies to bulk up their portfolios with little additional investment compared to only filing in the United States.

About ATMAC Patent Services Ltd.

ATMAC Patent Services Ltd. is a boutique patent firm based in Calgary, Alberta, Canada.

As a testament of client satisfaction, ATMAC provides ongoing patent services to start-ups, university technology transfer offices, and top tier international companies, as well as foreign patent firms and individuals located in the US, China, Europe.

ATMAC patent services are billed under a fixed-price model where you know the full cost upfront. There are no extra charges for after-the-fact items such as forwarding filing receipts and other correspondence to you from the patent Office.

If you have any questions about this white paper, about any particular differences between Canadian and US patent practice, or if you would like to work with ATMAC for filing a patent application in Canada or the US, we welcome your email or call.

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ps: You are also welcome to download a PDF version of this white paper: