United States: CAFC Affirms Finacea Gel Infringement Under Doctrine Of Equivalents

In Intendis GmbH v. Glenmark Pharmaceuticals Inc., USA, the Federal Circuit affirmed the district court decision that found infringement under the doctrine of equivalents. This case shows that the doctrine of equivalents still lives, that not every claim amendment will give rise to prosecution history estoppel, and that formulation patents can provide valuable protection for approved pharmaceutical products.

The Patent At Issue

The patent at issue was U.S. Patent No. 6,534,070, listed in the Orange Book for Finacea® Gel. The patent is owned by Intraserv GmbH & Co. and exclusively licensed to Intendis GmbH, both of whom were parties to the ANDA litigation.

Independent claim 1 recites:

A composition that comprises:
(i) azelaic acid as a therapeutically active ingredient in a concentration of 5 to 20% by weight,
(iii) at least one triacylglycerides in a concentration of 0.5 to 5% by weight,
(iv) propylene glycol, and
(v) at least one polysorbate, in an aqueous phase that further comprises water and salts,
and the composition further comprises
(ii) at least one polyacrylic acid, and
(vi) lecithin,
wherein the composition is in the form of a hydrogel.

Glenmark filed an Abbreviated New Drug Application (ANDA) seeking FDA approval of a generic version of Finacea® Gel that is formulated with isopropyl myristate instead of a triglyceride and lecithin.

The District Court Decision

The district court determined that Glenmark's product infringed the '070 patent under the doctrine of equivalents. In particular, the court applied the function-way-result test and determined that the isopropyl myristate in Glenmark's formulation performed substantially the same function as the triglyceride and lecithin in the claimed formulation.

The Federal Circuit Decision

The Federal Circuit decision was authored by Judge Moore and joined by Chief Judge Prost and Judge Taranto. As noted in the decision, "[e]ach prong of the function-way-result test is a factual determination" reviewed "for clear error."

According to the Federal Circuit decision, the district court's finding on the "function" prong was supported by expert testimony that the claimed excipients could act as penetration enhancers, that "nothing in the record" indicated they could not, and by "repeated statements" in Glenmark's ANDA that both Glenmark's excipient and the claimed excipients function as penetration enhancers.

Glenmark challenged the "same function" finding, emphasizing that the '070 patent does not disclose that lecithin and triglyceride act as penetration enhancers, and that Intendis described those components as "an emulsifier and an emollient, respectively" in its own submissions to the FDA. Glenmark also emphasized that "not a single literature reference in evidence identified lecithin or triglyceride as a penetration enhancer."

The Federal Circuit rejected the first argument, noting "We have never held that a patent must spell out a claim element's function, way, and result in order for the doctrine of equivalents to apply as to that element." Rather, "[t]he relevant inquiry is what the claim element's function in the claimed composition is to one of skill in the art, and a fact finder may rely on extrinsic evidence in making this factual determination."

Rejecting the second argument, the Federal Circuit stated:

Fatal to Glenmark's argument is its own ANDA submission to the FDA repeatedly referring to the claimed excipients (triglyceride and lecithin) as penetration enhancers.

The Hypothetical Claim Analysis

Glenmark also challenged the finding of infringement on the basis that it enlarged the claims in a manner that would impermissibly encompass the prior art. The Federal Circuit acknowledged this limitation on the doctrine of equivalents, but determined that it was not violated.

The Federal Circuit noted that a "hypothetical claim analysis" can be used "to determine whether an equivalent would impermissibly ensnare the prior art," but found that Glenmark was drafting its hypothetical claim too broadly. While the district court's hypothetical claim "included the claimed excipients and Glenmark's excipients," Glenmark's hypothetical claim included any penetration enhancer. The prior art reference cited by Glenmark disclosed an azelaic acid microemulsion having DMSO as a penetration enhancer, but did not disclose a composition having any of the penetration enhancers at issue.

The Federal Circuit approved of the scope of the district court's hypothetical claim (which literally encompassed Glenmark's product) and its finding that it did not read on the prior art.

The Prosecution History Estoppel Analysis

Glenmark also argued that prosecution history estoppel barred the finding of infringement under the doctrine of equivalents, because the applicants surrendered a lecithin-free composition during prosecution.

As stated by the Federal Circuit, "prosecution history estoppel can occur during prosecution in one of two ways, either (1) by making a narrowing amendment to the claim ("amendment-based estoppel") or (2) by surrendering claim scope through argument to the patent examiner ("argument- based estoppel")." The court also noted that "issues relating to the application of prosecution history estoppel" are reviewed de novo.

The Federal Circuit summarized the relevant prosecution history as follows:

[T]he examiner noted that two dependent claims, which recited a lecithin "concentration of up to 1%" and "concentration of up to 3%," respectively, could include zero lecithin. Applicants responded that those range limitations clearly did not include zero because they "are only in claims dependent on independent claims, which clearly require [lecithin]." J.A. 4386–87 (noting that the examiner's argument "is not well taken."). Regardless, applicants amended the two dependent claims to recite a lecithin "concentration of from more than 0 to 1%" and "concentration of from more than 0 to 3%," respectively, noting that they were "amended to expressly state what has already been made clear on the record."

The district court determined that the amendments at issue "were for clarification purposes," and "'not to disclaim formulations with zero lecithin,'" and so prosecution history estoppel did not bar the doctrine of equivalents. The Federal Circuit agreed:

Argument-based estoppel only applies when the prosecution history "evince[s] a clear and unmistakable surrender of subject matter." .... Applicants' clarifying statement ... did not clearly and unmistakably disavow claim scope to distinguish prior art.

Amendment-based estoppel does not apply because the amendment was not a narrowing amendment made to obtain the patent. Rather, this record demonstrates that the amendment to the dependent claims was a clarifying amendment .... and it does not give rise to prosecution history estoppel.

Thus, the Federal Circuit affirmed the finding of infringement under the doctrine of equivalents.

A Non-Infringing Generic Product

While it is possible to have a non-infringing generic product, this case illustrates the importance of having a rationale for non-infringement that is consistent with representations made to the FDA during the approval process. Here, the Federal Circuit took Glenmark to task for the inconsistent positions taken before the FDA and the court:

In a strange turn of events, Glenmark argued at oral argument to this court that its statements in its FDA submissions about the claimed excipients (triglyceride and lecithin) functioning as penetration enhancers should be rejected and cannot be evidence to support the district court's finding. It argued that "lecithin and triglycerides are not known to the art as penetration enhancers" and that its representation to the FDA that they do function as penetration enhancers was a "guess" and "wrong." Oral Argument at 10:49–13:38, Intendis GmbH v. Glenmark Pharm. Inc., No. 2015-1902 (Fed. Cir. Jan. 8, 2016), available at http://oralarguments.cafc.uscourts.gov/default.aspx?fl=2015-1902.mp3. These seemingly extemporaneous arguments do not persuade us that there is clear error in the district court's decision that isopropyl myristate in Glenmark's generic product and the claimed triglyceride and lecithin perform substantially the same function. No such arguments were made by Glenmark in any of its briefing to this court. And when asked whether Glenmark had notified the FDA of these purported inaccurate representations to the FDA, Glenmark's counsel was unaware of such notification. Id. at 11:53 -12:25.

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 Mondaq.com.

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

Similar Articles
Relevancy Powered by MondaqAI
McDermott Will & Emery
In association with
Related Topics
Similar Articles
Relevancy Powered by MondaqAI
McDermott Will & Emery
Related Articles
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
Registration (you must scroll down to set your data preferences)

Mondaq Ltd requires you to register and provide information that personally identifies you, including your content preferences, for three primary purposes (full details of Mondaq’s use of your personal data can be found in our Privacy and Cookies Notice):

  • To allow you to personalize the Mondaq websites you are visiting to show content ("Content") relevant to your interests.
  • To enable features such as password reminder, news alerts, email a colleague, and linking from Mondaq (and its affiliate sites) to your website.
  • To produce demographic feedback for our content providers ("Contributors") who contribute Content for free for your use.

Mondaq hopes that our registered users will support us in maintaining our free to view business model by consenting to our use of your personal data as described below.

Mondaq has a "free to view" business model. Our services are paid for by Contributors in exchange for Mondaq providing them with access to information about who accesses their content. Once personal data is transferred to our Contributors they become a data controller of this personal data. They use it to measure the response that their articles are receiving, as a form of market research. They may also use it to provide Mondaq users with information about their products and services.

Details of each Contributor to which your personal data will be transferred is clearly stated within the Content that you access. For full details of how this Contributor will use your personal data, you should review the Contributor’s own Privacy Notice.

Please indicate your preference below:

Yes, I am happy to support Mondaq in maintaining its free to view business model by agreeing to allow Mondaq to share my personal data with Contributors whose Content I access
No, I do not want Mondaq to share my personal data with Contributors

Also please let us know whether you are happy to receive communications promoting products and services offered by Mondaq:

Yes, I am happy to received promotional communications from Mondaq
No, please do not send me promotional communications from Mondaq
Terms & Conditions

Mondaq.com (the Website) is owned and managed by Mondaq Ltd (Mondaq). Mondaq grants you a non-exclusive, revocable licence to access the Website and associated services, such as the Mondaq News Alerts (Services), subject to and in consideration of your compliance with the following terms and conditions of use (Terms). Your use of the Website and/or Services constitutes your agreement to the Terms. Mondaq may terminate your use of the Website and Services if you are in breach of these Terms or if Mondaq decides to terminate the licence granted hereunder for any reason whatsoever.

Use of www.mondaq.com

To Use Mondaq.com you must be: eighteen (18) years old or over; legally capable of entering into binding contracts; and not in any way prohibited by the applicable law to enter into these Terms in the jurisdiction which you are currently located.

You may use the Website as an unregistered user, however, you are required to register as a user if you wish to read the full text of the Content or to receive the Services.

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 or with the prior written consent of Mondaq. You may not use electronic or other means to extract details or information from the Content. Nor shall you extract information about users or Contributors in order to offer them any services or products.

In your use of the Website and/or Services you shall: comply with all applicable laws, regulations, directives and legislations which apply to your Use of the Website and/or Services in whatever country you are physically located including without limitation any and all consumer law, export control laws and regulations; provide to us true, correct and accurate information and promptly inform us in the event that any information that you have provided to us changes or becomes inaccurate; notify Mondaq immediately of any circumstances where you have reason to believe that any Intellectual Property Rights or any other rights of any third party may have been infringed; co-operate with reasonable security or other checks or requests for information made by Mondaq from time to time; and at all times be fully liable for the breach of any of these Terms by a third party using your login details to access the Website and/or Services

however, you shall not: do anything likely to impair, interfere with or damage or cause harm or distress to any persons, or the network; do anything that will infringe any Intellectual Property Rights or other rights of Mondaq or any third party; or use the Website, Services and/or Content otherwise than in accordance with these Terms; use any trade marks or service marks of Mondaq or the Contributors, or do anything which may be seen to take unfair advantage of the reputation and goodwill of Mondaq or the Contributors, or the Website, Services and/or Content.

Mondaq reserves the right, in its sole discretion, to take any action that it deems necessary and appropriate in the event it considers that there is a breach or threatened breach of the Terms.

Mondaq’s Rights and Obligations

Unless otherwise expressly set out to the contrary, nothing in these Terms shall serve to transfer from Mondaq to you, any Intellectual Property Rights owned by and/or licensed to Mondaq and all rights, title and interest in and to such Intellectual Property Rights will remain exclusively with Mondaq and/or its licensors.

Mondaq shall use its reasonable endeavours to make the Website and Services available to you at all times, but we cannot guarantee an uninterrupted and fault free service.

Mondaq reserves the right to make changes to the services and/or the Website or part thereof, from time to time, and we may add, remove, modify and/or vary any elements of features and functionalities of the Website or the services.

Mondaq also reserves the right from time to time to monitor your Use of the Website and/or services.


The Content is general information only. It is not intended to constitute legal advice or seek to be the complete and comprehensive statement of the law, nor is it intended to address your specific requirements or provide advice on which reliance should be placed. Mondaq and/or its Contributors and other suppliers make no representations about the suitability of the information contained in the Content for any purpose. All Content provided "as is" without warranty of any kind. Mondaq and/or its Contributors and other suppliers hereby exclude and disclaim all representations, warranties or guarantees with regard to the Content, including all implied warranties and conditions of merchantability, fitness for a particular purpose, title and non-infringement. To the maximum extent permitted by law, Mondaq expressly excludes all representations, warranties, obligations, and liabilities arising out of or in connection with all Content. In no event shall Mondaq 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 of the Content or performance of Mondaq’s Services.


Mondaq may alter or amend these Terms by amending them on the Website. By continuing to Use the Services and/or the Website after such amendment, you will be deemed to have accepted any amendment to these Terms.

These Terms shall be governed by and construed in accordance with the laws of England and Wales and you irrevocably submit to the exclusive jurisdiction of the courts of England and Wales to settle any dispute which may arise out of or in connection with these Terms. If you live outside the United Kingdom, English law shall apply only to the extent that English law shall not deprive you of any legal protection accorded in accordance with the law of the place where you are habitually resident ("Local Law"). In the event English law deprives you of any legal protection which is accorded to you under Local Law, then these terms shall be governed by Local Law and any dispute or claim arising out of or in connection with these Terms shall be subject to the non-exclusive jurisdiction of the courts where you are habitually resident.

You may print and keep a copy of these Terms, which form the entire agreement between you and Mondaq and supersede any other communications or advertising in respect of the Service and/or the Website.

No delay in exercising or non-exercise by you and/or Mondaq of any of its rights under or in connection with these Terms shall operate as a waiver or release of each of your or Mondaq’s right. Rather, any such waiver or release must be specifically granted in writing signed by the party granting it.

If any part of these Terms is held unenforceable, that part shall be enforced to the maximum extent permissible so as to give effect to the intent of the parties, and the Terms shall continue in full force and effect.

Mondaq shall not incur any liability to you on account of any loss or damage resulting from any delay or failure to perform all or any part of these Terms if such delay or failure is caused, in whole or in part, by events, occurrences, or causes beyond the control of Mondaq. Such events, occurrences or causes will include, without limitation, acts of God, strikes, lockouts, server and network failure, riots, acts of war, earthquakes, fire and explosions.

By clicking Register you state you have read and agree to our Terms and Conditions