United States: Federal Circuit Provides Additional Guidance In Reversing Holding Of Patent-Ineligibility Of Biotech Invention

Although it is not yet a bright line, the Federal Circuit has considerably decreased the fuzziness of the distinction between patent-eligible and patent-ineligible inventions, at least where the exception to 35 U.S.C. § 101 is a law of nature. In Rapid Litigation Management Ltd. v. Cellzdirect, Inc., Appeal No. 2015-1570 (Fed. Cir. July 5, 2016), the Federal Circuit reversed the district court's holding of invalidity under § 101, ruling that the district court erred in applying both step 1 and step 2 of the Supreme Court's framework for determining patent eligibility. See Alice Corp. v. CLS Bank Int'l, 134 S. Ct. 2347, 2355 (2014).

The district court held that the patent in suit is directed to a law of nature—that hepatocytes, a type of liver cell, are capable of surviving multiple freeze-thaw cycles—and that the patented process lacks the requisite inventive concept. Hepatocytes have a number of uses, such as for investigating how drugs may be metabolized by the liver or measuring a drug's effect on liver biology, but their availability is limited and their life span is short. The prior art disclosed freezing hepatocytes ("cryopreservation"), thawing them when needed, and recovering the viable cells using density gradient fractionation, but persons of ordinary skill in the art understood that that process could damage the cells and lead to poor recoveries of viable cells. Moreover, pooled samples from multiple donors, desirable to create a collection of cells approximating average liver cells, could be created only by accumulating and freezing cells from single donors and then thawing and combining them for immediate use. Those skilled in the art believed that cryopreservation could be employed only once, and cryopreservation could damage cells, which severely limited the creation of pooled cells.

The inventors' discovery was a law of nature: that a fraction of hepatocytes can survive multiple freeze-thaw cycles. Based on that discovery, the inventors claimed a method of producing a collection of hepatocytes by subjecting previously frozen and thawed cells to fractionation to separate and recover viable cells, and refreezing the viable cells, which, after being thawed again, exhibit 70 percent viability. Thus, claim 1 recites:

  1. A method of producing a desired preparation of multi-cryopreserved hepatocytes, said hepatocytes being capable of being frozen and thawed at least two times, and in which greater than 70% of the hepatocytes of said preparation are viable after the final thaw, said method comprising:

(A) subjecting hepatocytes that have been frozen and thawed to density gradient fractionation to separate viable hepatocytes from nonviable hepatocytes,

(B) recovering the separated viable hepatocytes, and

(C) cryopreserving the recovered viable hepatocytes to thereby form said desired preparation of hepatocytes without requiring a density gradient step after thawing the hepatocytes for the second time, wherein the hepatocytes are not plated between the first and second cryopreservations, and wherein greater than 70% of the hepatocytes of said preparation are viable after the final thaw.

Claim 5 depends on claim 1 and limits the "preparation" to a pooled preparation of cells from multiple sources.

The patented process enables the production of cells that can be thawed later with sufficient viability, and for the first time permits refreezing of pooled hepatocyte preparations for later use. The district court, however, invalidated the claims under § 101 as directed to a law of nature (step 1) and as simply reapplying "a well-understood freezing process" (step 2).

The Federal Circuit accorded no deference to the district court, noting that patent eligibility is a question of law. Its reasoning in reversing the district court on both steps 1 and 2 reveals important factors in determination of the issue.

One factor, applicable to all of the exceptions to § 101, is whether the claimed invention preempts the natural phenomena, abstract idea, or law of nature. "The concern underlying these judicial exclusions is that 'patent law not inhibit further discovery by improperly tying up the future use of these building blocks of human ingenuity.'" Slip op. at 7 (quoting Mayo Collaborative Servs. v. Prometheus Labs., Inc., 132 S. Ct. 1289, 1301 (2012)). Regarding step 1, the court emphasized that the exception applies only if the claims are "directed to" a patent-ineligible concept. The court reasoned that the patented claims on appeal are directed to a laboratory technique for preserving hepatocytes, not the law of nature, i.e. the ability of hepatocytes to survive multiple freeze-thaw cycles. Instead, the inventors "employed their natural discovery to create a new and improved way of preserving hepatocyte cells for later use." Slip op. at 9. Moreover, the court relied on the district court's finding that the patent in suit did not preempt the natural law as confirming its conclusion under step 1. Slip op. at 16-17. Thus, whether a claim is "directed to" a patent-ineligible concept appears to be closely related to whether it preempts the concept.

The court distinguished cases it had held to have patent-ineligible claims. Those cases, the court said, had claims that required merely observing or identifying the ineligible concept itself. Id. In Genetic Techs., Ltd. v. Merial L.L.C., 18 F.3d 1369, 1373-74 (Fed. Cir. 2016), the court explained, the patent claimed detecting a coating region of DNA based on its relationship to non-coating regions, the relationship constituting a law of nature. Consequently, "the claim amounted to nothing other than identifying 'information about a patient's natural genetic makeup.'" Slip op. at 9 (quoting Genetic Techs. at 1375). Similarly, the court explained that in Ariosa Diagnostics, Inc. v. Sequenom, Inc., 788 F.3d 1371, 1373-74 (Fed. Cir. 2015), cert. denied, No. 15-1102, 2016 WL 1117246 (June 27, 2016), the patent-ineligible claims recited methods for detecting paternally inherited cffDNA in the blood of a pregnant female, and because the existence of cffDNA is a natural phenomenon, detecting it was "claiming the natural phenomena itself." Slip op. at 9. And regarding the claims in In re BRCA1- & BRCA2-Based Hereditary Cancer Test Patent Litig., 774 F.3d 755, 761-62 (Fed. Cir. 2014), the court reasoned that "comparing two sequences to detect alterations is a patent-ineligible 'abstract mental process.'" Slip op. at 9 (quoting id. at 763) (emphasis added). The "essence of the whole" in each of those cases, according to the court, was a patent-ineligible concept. Slip op. at 9-10.

By contrast, the court noted that the patent claims before it were "directed to a new and useful method of preserving hepatocyte cells," not just the ability of the cells to survive multiple freeze-thaw cycles. Slip op. at 10 (emphasis added). The patent claims

are like thousands of others that recite processes to achieve a desired outcome, e.g., methods of producing things, or methods of treating disease. That one way of describing the process is to describe the natural ability of the subject matter to undergo the process does not make the claim "directed to" that natural ability. If that were so, we would find patent-ineligible methods of, say, producing a new compound (as directed to the individual components' ability to combine to form the new compound) . . . .

Slip op. at 10.

Regarding the pooling of cells required by claim 5, the court relied on the difference between product and process claims. The court distinguished Funk Bros. Co. v. Kalo Innoculant Co., 333 U.S. 127 (1948), where the Supreme Court held that a mixture of different bacterial species was not patent eligible because each species in the mixture performed in its natural way, by observing that Funk Bros. involved product claims while in the case before it "the claims are directed to a new and useful process of creating that pool, not to the pool itself." Slip op. at 11. The court noted that in Ass'n for Molecular Pathology v. Myriad Genetics, Inc., 133 S. Ct. 2107, 2116 (2013), the Supreme Court similarly observed that that case held composition claims to isolated DNA ineligible and that "[h]ad Myriad created an innovative method of manipulating genes . . . it could have possibly sought a method patent." Slip op. at 11 (quoting Myriad, 133 S. Ct. at 2119-20) (emphasis added). In the case before it, the Federal Circuit reasoned, "the inventors developed an innovative method of manipulating hepatocytes . . . ." Slip op. at 11 (emphasis added).

The court concluded regarding step 1 by emphasizing that mere involvement of a patent-ineligible concept does not invoke the prohibition of step 1 if the claim is not "directed to" the patent-ineligible concept. The patent in suit, the court reasoned, "does not simply claim hepatocytes' ability to survive multiple freeze-thaw cycles," but "instead claims a 'method of producing a desired preparation of multi-cryopreserved hepatocytes.'" Slip op. at 13 (quoting claim 1).

Having held that the district court erred in its holding regarding step 1, the Federal Circuit could of course have stopped. Perhaps to provide additional guidance in this developing area of the law, however, the court proceeded to explain why the district court also erred regarding step 2. The Federal Circuit reasoned that the claimed process improved an existing technological process sufficiently to transform it into an inventive application of what the defendants alleged was a patent-ineligible concept. The claims "recite an improved process for preserving hepatocytes for later use. The benefits of the improved process over the prior art methods are significant. . . . The claimed method is patent eligible because it applies the discovery that hepatocytes can be twice frozen to achieve a new and useful preservation process." Slip op. at 13-14.

The court rejected the argument that because each claimed step was known individually, the combination of steps did not make the claim patent eligible. It explained, "in examining claims under step two, we must view them as a whole, considering their elements 'both individually and as an ordered combination.'" Slip op. at 14 (quoting Alice, 134 S. Ct. at 2355) (internal quotations and citation omitted). The court reasoned that although freezing and thawing were well known, "[r]epeating a step that the art taught should be performed only once can hardly be considered routine or conventional. This is true even though it was the inventor's [sic] discovery of something natural that led them to do so. . . . To require something more at step two would be to discount the human ingenuity that comes from applying a natural discovery in a way that achieves a 'new and useful end.'" Slip op. at 15-16 (quoting Alice, 134 S. Ct. at 2354).

Finally, the court made two important observations. First, "patent-eligibility does not turn on ease of execution or obviousness of application" once the natural law was discovered. "Those are questions that are examined under separate provisions of the Patent Act." Slip op. at 16 (citing Mayo, 132 S. Ct. at 1304). Second, the court relied on the district court's finding that the patent in suit did not preempt the natural law and that the defendant had already managed to design around the patent. "[W]hile pre-emption is not the test for determining patent-eligibility . . ., it is certainly the 'concern that undergirds . . . § 101 jurisprudence,' Alice, 134 S. Ct. at 2358." Slip op. at 16. As noted above, the court asserted that the lack of preemption confirmed its conclusion that the patent is not "directed to" a patent-ineligible law of nature. Slip op. at 16-17.

In summary, key points from the case appear to be:

  1. Claims that do not preempt one of the exceptions to § 101 tend to be patent eligible.
  2. Mere involvement of a law of nature, and perhaps natural phenomena or abstract ideas, does not render a claimed invention patent ineligible unless the claims are "directed to" one of those exception to § 101. A claim that simply recites a law of nature is likely "directed to" that law of nature.
  3. A claim that applies a law of nature or abstract mental process merely by reciting a step of observing, identifying, detecting, or comparing may be held to be "directed to" the law of nature or abstract mental process.
  4. But a claimed method that goes further and applies a law of nature to achieve a better way of producing something or treating disease will likely qualify for patent protection.
  5. In applying step 2, that all of the claimed steps individually were well known does not disqualify a process from patenting if the combination of steps is new and therefore not routine and conventional.
  6. That a patented process would have been obvious once the law of nature was discovered does not render the process patent ineligible, but rather depends on application of § 103.
  7. Preemption vel non, although not conclusive, is an important factor in determining patent eligibility.

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
Cadwalader, Wickersham & Taft LLP
Stroock & Stroock & Lavan LLP
In association with
Related Topics
Similar Articles
Relevancy Powered by MondaqAI
Cadwalader, Wickersham & Taft LLP
Stroock & Stroock & Lavan LLP
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