Canada: Misstatements And Inequitable Conduct In Canada After Weatherford

Last Updated: January 6 2012
Article by Beverley Moore and Chantal Saunders

Most Read Contributor in Canada, September 2016

In Canada, there are two main provisions in the Patent Act which relate to the conduct of a party when obtaining a patent. Section 53(1) relates to misrepresentations to the Patent Office and section 73(1)(a) relates to good faith responses to the Examiner. The provisions read as follows:

53. (1) A patent is void if any material allegation in the petition of the applicant in respect of the patent is untrue, or if the specification and drawings contain more or less than is necessary for obtaining the end for which they purport to be made, and the omission or addition is willfully made for the purpose of misleading.

73. (1) An application for a patent in Canada shall be deemed to be abandoned if the applicant does not

(a) reply in good faith to any requisition made by an examiner in connection with an examination, within six months after the requisition is made or within any shorter period established by the Commissioner.1

In recent years, the Federal Court considered a few cases where a party raised issues of a lack of good faith and/or material misrepresentation as part of their challenges to the validity of the patent in suit.

The decisions resulting from these cases were of great concern to patentees, as they seemed to invoke changes in the law as it had previously existed. However, the Federal Court of Appeal made several more recent decisions, clarifying this issue.


The Federal Court, in a Notice of Compliance (NOC) Proceeding, considered the Patent Act, and held that "[t]here is no provision in the Patent Act or Rules that directly provides to a third party a right to invalidate a patent for fraud or lack of good faith during prosecution of the application."2 However, the Court then considered the American law relating to inequitable conduct, the Australian law relating to fraud or misrepresentation, the history of section 73 and the doctrine of good faith prior to its implementation in 1996.

The Court held that obtaining a patent was an ex parte proceeding. During prosecution, responses must be full, frank and fair, and there is ample opportunity to correct mistakes.3 Furthermore, it "is not harsh or unreasonable, if after the patent issues, and disclosure is found to lack good faith, that the Court deems the application and thus the patent, to have been abandoned."4

Following Searle was a decision in Lundbeck5 where the Court again considered an allegation that the patent was abandoned during prosecution due to a response to an office action that was allegedly not made in good faith. The factual situation related to a particular piece of prior art. The article in question, Wenk, was mentioned in an International Search Report. However, when the Examiner issued an office action, arguing that the invention was obvious, he did not cite the Wenk article. In the response to the obviousness objection, the patent agent responded to the art cited, then cited several other pieces of art and concluded with a statement that:

In fact, in view of the prior art, which showed that NMDA antagonists attenuate the effect of AChE, it was not obvious for a skilled person to arrive at the present invention. Indeed, the prior art clearly teaches away from the combination of a NMDA antagonist with an AChE inhibitor as claimed in the instant application. [emphasis added by Court]6

The patent issued and was challenged in a proceeding under the Patented Medicines

(Notice of Compliance) Regulations (the NOC Regulations). The generic company alleged that the patent was abandoned pursuant to section 73 of the Patent Act due to a lack of good faith response to the office action based on the failure to discuss the Wenk article.

The Court held that the allegations of invalidity were justified. The Judge looked at the objection and the response and considered that the Wenk article was cited in neither. However, the Judge was concerned with the patent agent's statement about the general state of the art and found that the response was not made in good faith, given the existence of the Wenk article. It is worth noting that the Judge in this same case considered the Wenk article in her obviousness analysis and found that the allegations of obviousness were not justified. No appeal was possible from this case as the generic company received its marketing authorization, rendering any appeal moot.7

Thus, this case caused concern to many agents who may have used what could be interpreted as similarly broad language in their responses to office actions. Despite the fact that the Federal Court of Appeal has held that cases decided under the NOC Regulations are not to be precedential,8 many are applied by both the Court and the Patent Office as binding law.

Consequently, it appeared that the United States doctrine of inequitable conduct was finding its way into Canadian law. At this same time, inequitable conduct was being commonly asserted successfully in the United States and patentees and patent agents were being held to a very high standard, often long after the patent had issued.

Furthermore, this doctrine as defined by Searle and Lundbeck would be applied to patents that had been prosecuted at a time when section 73 was not used in this manner. Indeed, section 73 as it currently stands was not introduced into the Patent Act until 1996; so many of the patents it could be used against were prosecuted when this provision did not exist.

However, the Federal Court and the Federal Court of Appeal recently issued a decision overruling these cases. The Federal Court of Appeal held that section 53 applies to issued patents while section 73 applies to patent applications:9

To be clear, the concept of abandonment in paragraph 73(1)(a) operates during the prosecution of the application for a patent. Its operation is extinguished once the patent issues.

Post-issuance, the provisions of subsection 53(1) must be utilized with respect to allegations of misrepresentation. To conclude otherwise would result in absurdity. An issued patent would be subject to retroactive scrutiny by the courts in relation to the submissions made by an applicant to the Patent Office during prosecution (generally many years prior), judged against unknown criteria. It is for the Commissioner to determine whether an applicant's response to a requisition from an Examiner is made in good faith, not for the courts. The courts do not issue patents.10

The Federal Court of Appeal also explicitly held that the Court's decisions in Lundbeck and Searle "should not be followed" to the extent that they stand for the proposition that section 73 can be relied upon for the purpose of attacking the validity of a patent.11

As a result of this very conclusive statement by the Federal Court of Appeal, it is expected that more stability will return to patent law in Canada. Patentees are still obliged by law to respond in good faith to requisitions from the Patent Office. However, third parties will not be able to challenge those decisions after the fact.

This is more consistent with the recent changes in the United States, which have made it more difficult for third parties to succeed on inequitable conduct challenges. Inequitable conduct is codified and has become a common ground of attack. However, recently, after an en banc hearing, the Court of Appeals for the Federal Circuit described this doctrine as "the 'atomic bomb' of patent law."12 The Court then held that, as a general rule, the doctrine should only be applied where the patentee's misconduct resulted in the patentee unfairly receiving an unwarranted claim, as there is no injury to the public by the enforcement of an otherwise valid patent simply because there may be misconduct lurking in the prosecution that was not material to issuance.13 This is also described as "but-for materiality" and is to be applied generally except in cases of affirmative egregious misconduct.14 This increased standard of proof for inequitable conduct allegations in the United States is expected to reduce the number of successful challenges to patent validity.


Allegations of material misstatement were also made in a number of cases pursuant to the Patented Medicines (Notice of Compliance) Regulations. However, these allegations were rarely argued at the hearing and were never successful.15 Moreover, the Court started imposing significant cost consequences where unsuccessful allegations pursuant to section 53 were raised. In particular, even if the generic company was otherwise successful in their allegations, in later cases, their fees were reduced by 25% if section 53 was alleged and not proven.16 However, in an impeachment action that followed a successful NOC proceeding, the allegations pursuant to section 53 were allowed.17 Three material misstatements were explicitly alleged by the plaintiff in the pleadings, and a fourth was argued to be implied. The Court held that implication was not good enough and that allegations pursuant to section 53 must be pleaded with particularity.18 The Court then held that misstatements were made, that they enhanced the characteristics of the claimed salt, and that those enhanced characteristics were not true.19 Furthermore, the patent agents distanced themselves from the drafting of the patent.20 The Court held that an intent to mislead can be inferred.21

The Court of Appeal upheld the ruling that the patent was invalid, but did not explicitly consider the trial Judge's comments on section 53, and instead found the determination to be "confined to the unique and particular circumstances of this matter. It has limited, if any, value as a precedent."22

Weatherford touched on this issue; however, the comments were made in the context of allegations that an inventor was intentionally misnamed. The Court of Appeal was reluctant to infer a willful misleading statement (and the draconian remedy that would result) in the absence of a fulsome analysis by the Trial Judge on the issue.23 The Court of Appeal also commented it would be an anomalous result for other, unnamed, inventors to lose their rights to the patent rather than to be granted access to what they had previously been denied.24

In the end, the Court of Appeal upheld the Trial Judge's decision that the alleged inventor in

question was not in fact an inventor. Thus, s. 53 was not an issue.

At this time, it is difficult to say what the Court will consider to qualify as a material misrepresentation made for the purpose of misleading. The ultimate success of such allegations will largely depend on the factual circumstances of any particular case, making it difficult for patentees to properly evaluate the likelihood of success of such an allegation. However, because of the cost consequences that the Court appears to be imposing in NOC proceedings in respect of an allegation relating to material misrepresentation that is withdrawn, these allegations are being put forward less frequently.


Good faith and material misrepresentations remain part of the law in Canada. This is important as these principles provide a valuable check and balance against fraudulent conduct by inventors. However, it is equally important that the standard of proof be high in order for a patent to be invalidated under the material misrepresentation doctrine in order to prevent frivolous accusations being made by defendants in infringement cases.


1 Patent Act, RSC 1985, c P-4, s 73.

2 GD Searle & Co v Novopharm Ltd, 2007 FC 81 at para 61, [2008] 1 FCR 477 (FC); reversed 2007 FCA 173 (FCA) on other grounds with no comment on this issue.

3 Ibid at para 72.

4 Ibid at para 73.

5 Lundbeck Canada Inc v ratiopharm Inc, 2009 FC 1102, 79 CPR (4th) 243 (FC).

6 Ibid at para 311.

7 The Courts have held that once the prohibition application is dismissed, the Minister of Health is lawfully able to issue a NOC (marketing authorization) to a generic company, and once that happens, there is no longer anything to prohibit. Furthermore, there is no provision under the NOC Regulations to address this situation. See Pfizer Canada Inc v Apotex Inc (2001), 11 CPR (4th) 245, 266 NR 371 (FCA).

8 Eli Lilly Canada Inc v Novopharm Limited, 2007 FCA 359 at para 41, [2008] 3 FCR 449 (FCA).

9 Corlac Inc v Weatherford Canada Inc, 2011 FCA 228, at para 149, 95 CPR (4th) 101 (FCA) [Weatherford ].

10 Ibid at para 150.

11 Ibid at para 151.

12 Therasense v Becton, 649 F (3d) 1276 (CAFC 2011) [Therasense ].

13 Ibid.

14 Ibid.

15 See Eli Lilly Canada Inc v Apotex Inc, 2007 FC 455, 58 CPR (4th) 353 (FC) aff'd 2008 FCA 44 (FCA); Eli Lilly Canada Inc v Novopharm Ltd, 2007 FC 596, 58 CPR (4th) 214 (FC); Shire Biochem Inc v Canada (Minister of Health) 2008 FC 538, 67 CPR (4th) 94 (FC); Bristol-Myers Squibb Co v Apotex Inc, 2009 FC 137, 74 CPR (4th) 85 (FC).

16 Ibid.

17 ratiopharm Inc v Pfizer Limited, 2009 FC 711, 76 CPR (4th) 241 (FC); affirmed with no comment on this point 2010 FCA 204 (FCA); although these allegations were discussed in obiter, the Court having already found the patent invalid for obviousness [ratiopharm].

18 Ibid at paras 196-198.

19 Ibid at para 199.

20 Ibid at para 200.

21 Ibid at para 204.

22 ratiopharm Inc v Pfizer Ltd, 2010 FCA 204 at para 34, 87 CPR (4th) 185 (FCA).

23 Weatherford, supra at para 120.

24 Ibid at para 123.

About BLG

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

To print this article, all you need is to be registered on

Click to Login as an existing user or Register so you can print this article.

In association with
Related Video
Up-coming Events Search
Font Size:
Mondaq on Twitter
Register for Access and our Free Biweekly Alert for
This service is completely free. Access 250,000 archived articles from 100+ countries and get a personalised email twice a week covering developments (and yes, our lawyers like to think you’ve read our Disclaimer).
Email Address
Company Name
Confirm Password
Mondaq Topics -- Select your Interests
 Law Performance
 Law Practice
 Media & IT
 Real Estate
 Wealth Mgt
Asia Pacific
European Union
Latin America
Middle East
United States
Worldwide Updates
Check to state you have read and
agree to our Terms and Conditions

Terms & Conditions and Privacy Statement (the Website) is owned and managed by Mondaq Ltd and as a user you are granted a non-exclusive, revocable license to access the Website under its terms and conditions of use. Your use of the Website constitutes your agreement to the following terms and conditions of use. Mondaq Ltd may terminate your use of the Website if you are in breach of these terms and conditions or if Mondaq Ltd decides to terminate your license of use for whatever reason.

Use of

You may use the Website but are required to register as a user if you wish to read the full text of the content and articles available (the Content). You may not modify, publish, transmit, transfer or sell, reproduce, create derivative works from, distribute, perform, link, display, or in any way exploit any of the Content, in whole or in part, except as expressly permitted in these terms & conditions or with the prior written consent of Mondaq Ltd. You may not use electronic or other means to extract details or information about’s content, users or contributors in order to offer them any services or products which compete directly or indirectly with Mondaq Ltd’s services and products.


Mondaq Ltd and/or its respective suppliers make no representations about the suitability of the information contained in the documents and related graphics published on this server for any purpose. All such documents and related graphics are provided "as is" without warranty of any kind. Mondaq Ltd and/or its respective suppliers hereby disclaim all warranties and conditions with regard to this information, including all implied warranties and conditions of merchantability, fitness for a particular purpose, title and non-infringement. In no event shall Mondaq Ltd and/or its respective suppliers be liable for any special, indirect or consequential damages or any damages whatsoever resulting from loss of use, data or profits, whether in an action of contract, negligence or other tortious action, arising out of or in connection with the use or performance of information available from this server.

The documents and related graphics published on this server could include technical inaccuracies or typographical errors. Changes are periodically added to the information herein. Mondaq Ltd and/or its respective suppliers may make improvements and/or changes in the product(s) and/or the program(s) described herein at any time.


Mondaq Ltd requires you to register and provide information that personally identifies you, including what sort of information you are interested in, for three primary purposes:

  • To allow you to personalize the Mondaq websites you are visiting.
  • To enable features such as password reminder, newsletter alerts, email a colleague, and linking from Mondaq (and its affiliate sites) to your website.
  • To produce demographic feedback for our information providers who provide information free for your use.

Mondaq (and its affiliate sites) do not sell or provide your details to third parties other than information providers. The reason we provide our information providers with this information is so that they can measure the response their articles are receiving and provide you with information about their products and services.

If you do not want us to provide your name and email address you may opt out by clicking here .

If you do not wish to receive any future announcements of products and services offered by Mondaq by clicking here .

Information Collection and Use

We require site users to register with Mondaq (and its affiliate sites) to view the free information on the site. We also collect information from our users at several different points on the websites: this is so that we can customise the sites according to individual usage, provide 'session-aware' functionality, and ensure that content is acquired and developed appropriately. This gives us an overall picture of our user profiles, which in turn shows to our Editorial Contributors the type of person they are reaching by posting articles on Mondaq (and its affiliate sites) – meaning more free content for registered users.

We are only able to provide the material on the Mondaq (and its affiliate sites) site free to site visitors because we can pass on information about the pages that users are viewing and the personal information users provide to us (e.g. email addresses) to reputable contributing firms such as law firms who author those pages. We do not sell or rent information to anyone else other than the authors of those pages, who may change from time to time. Should you wish us not to disclose your details to any of these parties, please tick the box above or tick the box marked "Opt out of Registration Information Disclosure" on the Your Profile page. We and our author organisations may only contact you via email or other means if you allow us to do so. Users can opt out of contact when they register on the site, or send an email to with “no disclosure” in the subject heading

Mondaq News Alerts

In order to receive Mondaq News Alerts, users have to complete a separate registration form. This is a personalised service where users choose regions and topics of interest and we send it only to those users who have requested it. Users can stop receiving these Alerts by going to the Mondaq News Alerts page and deselecting all interest areas. In the same way users can amend their personal preferences to add or remove subject areas.


A cookie is a small text file written to a user’s hard drive that contains an identifying user number. The cookies do not contain any personal information about users. We use the cookie so users do not have to log in every time they use the service and the cookie will automatically expire if you do not visit the Mondaq website (or its affiliate sites) for 12 months. We also use the cookie to personalise a user's experience of the site (for example to show information specific to a user's region). As the Mondaq sites are fully personalised and cookies are essential to its core technology the site will function unpredictably with browsers that do not support cookies - or where cookies are disabled (in these circumstances we advise you to attempt to locate the information you require elsewhere on the web). However if you are concerned about the presence of a Mondaq cookie on your machine you can also choose to expire the cookie immediately (remove it) by selecting the 'Log Off' menu option as the last thing you do when you use the site.

Some of our business partners may use cookies on our site (for example, advertisers). However, we have no access to or control over these cookies and we are not aware of any at present that do so.

Log Files

We use IP addresses to analyse trends, administer the site, track movement, and gather broad demographic information for aggregate use. IP addresses are not linked to personally identifiable information.


This web site contains links to other sites. Please be aware that Mondaq (or its affiliate sites) are not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of these third party sites. This privacy statement applies solely to information collected by this Web site.

Surveys & Contests

From time-to-time our site requests information from users via surveys or contests. Participation in these surveys or contests is completely voluntary and the user therefore has a choice whether or not to disclose any information requested. Information requested may include contact information (such as name and delivery address), and demographic information (such as postcode, age level). Contact information will be used to notify the winners and award prizes. Survey information will be used for purposes of monitoring or improving the functionality of the site.


If a user elects to use our referral service for informing a friend about our site, we ask them for the friend’s name and email address. Mondaq stores this information and may contact the friend to invite them to register with Mondaq, but they will not be contacted more than once. The friend may contact Mondaq to request the removal of this information from our database.


This website takes every reasonable precaution to protect our users’ information. When users submit sensitive information via the website, your information is protected using firewalls and other security technology. If you have any questions about the security at our website, you can send an email to

Correcting/Updating Personal Information

If a user’s personally identifiable information changes (such as postcode), or if a user no longer desires our service, we will endeavour to provide a way to correct, update or remove that user’s personal data provided to us. This can usually be done at the “Your Profile” page or by sending an email to

Notification of Changes

If we decide to change our Terms & Conditions or Privacy Policy, we will post those changes on our site so our users are always aware of what information we collect, how we use it, and under what circumstances, if any, we disclose it. If at any point we decide to use personally identifiable information in a manner different from that stated at the time it was collected, we will notify users by way of an email. Users will have a choice as to whether or not we use their information in this different manner. We will use information in accordance with the privacy policy under which the information was collected.

How to contact Mondaq

You can contact us with comments or queries at

If for some reason you believe Mondaq Ltd. has not adhered to these principles, please notify us by e-mail at and we will use commercially reasonable efforts to determine and correct the problem promptly.