United States: PTO Adopting But-For Materiality In Proposed Revision Of Duty To Disclose Rules

On October 28, 2016, the United States Patent and Trademark Office ("PTO") again proposed revisions to the materiality standard for the duty to disclose information in patent applications and reexamination proceedings. Revision of the Duty to Disclose Information in Patent Applications and Reexamination Proceedings, 81 Fed. Reg. 74,987 (proposed Oct. 28, 2016) (to be codified at 37 C.F.R. pt. 1) (hereinafter 2016 Proposed Revisions). The PTO sought to "harmonize the materiality standard for the duty of disclosure before the [PTO] with the but-for materiality standard for establishing inequitable conduct before the courts in light of the Federal Circuit's decision in Therasense, Inc. v. Becton, Dickinson & Co., 649 F.3d 1276 (Fed. Cir. 2011) (en banc)." Id. at 74988.

The PTO had previously proposed revisions to a similar effect on July 21, 2011 and received 24 written public comments. See Revision of the Materiality to Patentability Standard for the Duty to Disclose Information in Patent Applications, 76 Fed. Reg. 43,631 (proposed July 21, 2011) (hereinafter 2011 Proposed Revisions). However, the passage of time and the intervening implementation of the America Invents Act prompted the PTO to solicit further comments on the subject. See 2016 Proposed Revisions at 74,988.
In Therasense, the Federal Circuit held that ''the materiality required to establish inequitable conduct is but-for materiality.'' Therasense, 649 F.3d at 1291. The Federal Circuit clarified that "[w]hen an applicant fails to disclose prior art to the PTO, that prior art is but-for material if the PTO would not have allowed a claim had it been aware of the undisclosed prior art." Id. "[I]n assessing . . . whether the PTO would have allowed the claim if it had been aware of the undisclosed reference[,] . . . the court should apply the preponderance of the evidence standard and give claims their broadest reasonable construction." Id. at 1291–92. In addition, to deal with "'deliberately planned and carefully executed schemes' to defraud the PTO and the courts," the Federal Circuit recognized an "affirmative egregious misconduct" exception to the general rule of requiring but-for materiality. Id. at 1292.
Although Therasense does not require the PTO to revise its materiality standard, the PTO saw important reasons to do so. 2016 Proposed Revisions at 74,989. The PTO expected that the adoption of the but-for materiality standard in Therasense would reduce the number of inequitable conduct charges in front of the PTO and "reduce the incentive to submit marginally relevant information in information disclosure statements." Id. The PTO "also expect[ed] this currently proposed rule would continue to encourage applicants to comply with their duty of candor and good faith." Id. In particular, the PTO differentiated a pure but-for standard it rejected in 1992 from the currently proposed rule which includes the affirmative egregious misconduct exception. See id.
Specifically, the PTO now proposes to revise 37 C.F.R. § 1.56 to read as follows (with proposed revisions underlined):

§ 1.56 Duty to disclose information material to patentability.

(a) . . . Each individual associated with the filing and prosecution of a patent application has a duty of candor and good faith in dealing with the Office, which includes a duty to disclose to the Office all information known to that individual to be material to patentability under the but-for materiality standard as defined in paragraph (b) of this section. . . . However, no patent will be granted on an application in connection with which affirmative egregious misconduct was engaged in, fraud on the Office was practiced or attempted, or the duty of disclosure was violated through bad faith or intentional misconduct. . . .

(b) Information is but-for material to patentability if the Office would not allow a claim if the Office were aware of the information, applying the preponderance of the evidence standard and giving the claim its broadest reasonable construction consistent with the specification.

The PTO also proposes to revise 37 C.F.R. § 1.555 to read as follows (with proposed revisions underlined):

§ 1.555 Information material to patentability in ex parte reexamination and inter partes reexamination proceedings.

(a) . . . Each individual associated with the patent owner in a reexamination proceeding has a duty of candor and good faith in dealing with the Office, which includes a duty to disclose to the Office all information known to that individual to be material to patentability in a reexamination proceeding under the but-for materiality standard as defined in paragraph (b) of this section. . . . However, the duties of candor, good faith, and disclosure have not been complied with if affirmative egregious misconduct was engaged in, any fraud on the Office was practiced or attempted, or the duty of disclosure was violated through bad faith or intentional misconduct by, or on behalf of, the patent owner in the reexamination proceeding. . . .

(b) Information is but-for material to patentability if, for any matter proper for consideration in reexamination, the Office would not find a claim patentable if the Office were aware of the information, applying the preponderance of the evidence standard and giving the claim its broadest reasonable construction consistent with the specification.  

Note that 37 C.F.R. § 1.933, which is also directed to the duty of disclosure in inter partes reexamination proceedings, has not been amended herein because the statement as to materiality of information in § 1.933 incorporates § 1.555.
These revisions differ from the PTO's 2011 Proposed Revisions in several aspects:
First, in response to public comments raising potential confusion issues, the PTO moved the language regarding affirmative egregious misconduct from the definition of the materiality standard to § 1.56(a) and § 1.555(a). 2016 Proposed Revisions at 74,991; see also 2011 Proposed Revisions at 43,634.
Second, the currently proposed rule no longer explicitly refers to the Therasense decision in view of the public comments received. Id. at 74,989. However, the PTO did not intend to de-link the proposed rules with the Therasense decision despite this language change. Indeed, the PTO stated that "an explicit reference to the Therasense decision is not necessary to link the materiality standard for the duty of disclosure to the but-for materiality standard for inequitable conduct set forth in Therasense." Id. at 74,990. From the PTO's perspective, "the materiality standard for the duty of disclosure in this currently proposed rule is the same as the but-for materiality standard set forth in Therasense and its interpretations and applications." Id. at 74,989 (emphasis added). The PTO also relied on "Therasense and subsequent cases, as well as the lengthy jurisprudence of the unclean hands doctrine . . . [for] guidance as to the boundaries of affirmative egregious misconduct." Id. at 74,992. The PTO favored this approach because it "provid[es] a consistent materiality standard without the need for continuous revisions to the rules as the Therasense standard is interpreted or applied." Id. at 74,989. The PTO promised to reconsider the rules "[i]n the event the Supreme Court, or Federal Circuit acting en banc, [chose] to revise the but-for materiality standard in Therasense," and to "keep the public informed of its understanding of how the Federal Circuit interprets the standard through future revisions to the Manual of Patent Examining Procedure (MPEP)." Id.
Third, unlike the existing rule and the 2011 Proposed Revisions, § 1.555(b) as proposed does not limit the types of information that could be considered in a reexamination proceeding to patents and printed publications. Id. at 74,990. Rather, "the currently proposed rule encompasses disclosure of information as to any matter that is proper for consideration in a reexamination proceeding (e.g., admissions by patent owner)." Id.
Fourth, the PTO took a step back from its previous proposal considering incentivizing applicants "to assist the [PTO] by explaining/clarifying the relationship of prior art to the claimed invention." 2011 Proposed Revisions at 43,632. Several public comments argued that "the [PTO] should not require applicants to explain or clarify the relationship of the prior art to the claimed invention," and that "if the [PTO] requires such an explanation, applicants should be given a safe harbor . . . ." 2016 Proposed Revisions at 74,993. In response, the currently proposed rulemaking no longer includes the contemplated required explanation from the previous notice of proposed rulemaking. Id.
Finally, the PTO fixed an unintended omission by modifying the previously proposed rule language to state that a claim is given its broadest reasonable construction ''consistent with the specification.'' Id. at 74,990.
Although no public hearing will be held, the PTO is accepting public comments on the proposed rulemaking until December 27, 2016.

This article is intended to provide information of general interest to the public and is not intended to offer legal advice about specific situations or problems. Brinks Gilson & Lione does not intend to create an attorney-client relationship by offering this information and review of the information shall not be deemed to create such a relationship. You should consult a lawyer if you have a legal matter requiring attention. For further information, please contact a Brinks Gilson & Lione lawyer.

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

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

Mondaq.com (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 www.mondaq.com

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 Mondaq.com’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 unsubscribe@mondaq.com 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 webmaster@mondaq.com.

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 EditorialAdvisor@mondaq.com.

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 enquiries@mondaq.com.

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