USPTO Announces Guidance for Subject Matter Eligibility and Computer-Implemented Functional Claim Limitations

January 08, 2019

The US Patent and Trademark Office (USPTO) on January 4 announced the “2019 Revised Patent Subject Matter Eligibility Guidance” and “Computer-Implemented Functional Claim Limitations Guidance” for examiners and administrative patent judges.

2019 Revised Patent Subject Matter Eligibility Guidance

The Revised Patent Subject Matter Eligibility Guidance[1] focuses on the first step of the Alice/Mayo test[2]–that is, whether a claim is “directed to” a judicial exception to patentability (i.e., laws of nature, natural phenomena, and abstract ideas).[3]

The Revised Guidance sets forth a “two-prong inquiry” for determining if a claim is “directed to” an abstract idea. Initially, examiners must determine whether the claim limitation(s) “when recited on their own or per se” fall into certain enumerated categories of abstract ideas. If so, examiners then determine whether the claim recites additional elements that integrate the abstract idea into a practical application. Each of the two prongs is addressed below.

First, to “increase clarity and consistently in how Section 101 is currently applied,” the Revised Guidance provides groupings of subject matter considered to be an abstract idea.[4] These categories are the result of “extract[ing] and synthesiz[ing] key concepts identified by the courts as abstract ideas.”[5]

If an examiner believes claims that do not recite matter falling within these enumerated groupings should nevertheless be treated as reciting an abstract idea, the examiner may send a request for approval to the Technology Center Director with a justification for why such claim limitation is being treated as reciting an abstract idea.[6] Notably, the Revised Guidance notes that this will only occur in “the rare circumstance.”[7] Additionally, the Revised Guidance states that “in the rare circumstance in which a panel of administrative patent judges (or panel majority) believes that a claim reciting a tentative abstract idea should be treated as reciting an abstract idea, the matter should be brought to the attention of the [Patent Trial and Appeal Board] leadership by a written request for clearance.”[8]

Enumerated Category


Mathematical concepts

Mathematical relationships, mathematical formulas or equations, and mathematical calculations

Certain methods of organizing human activity

Fundamental economic principles or practices, including hedging, insurance, mitigating risk; commercial or legal interactions, including agreements in the form of contracts; legal obligations; advertising, marketing or sales activities or behaviors; business relations; managing personal behavior or relationships or interactions between people, including social activities, teaching, and following rules or instructions

Mental processes

Concepts performed in the human mind, including an observation, evaluation, judgment, and opinion


For this category, the Revised Guidance specifically notes that “[i]f a claim, under its broadest reasonable interpretation, covers performance in the mind but for the recitation of generic computer components, then it is still in the mental processes category unless the claim cannot practically be performed in the mind…. Likewise, performance of a claim limitation using generic computer components does not necessarily preclude the claim limitation from being in the mathematical concepts grouping, Benson, 409 U.S. at 67, or the certain methods of organizing human activity grouping, Alice, 573 U.S. at 219-20.”[9]

Second, if the claim falls within one of the above-mentioned categories, examiners must then determine whether the claim recites additional elements that integrate the identified judicial exception into a practical application. The Revised Guidance provides specific indicia of the additional elements being integrated into a practical application.[10] If a claim recites a judicial exception and fails to integrate that exception into a practical application, then the claim is “directed to” a judicial exception and the established second step of the Alice/Mayo test should be employed.

Examples from the Revised Guidance of circumstances where the judicial exception has been integrated into a practical application include:

Additional Element

Exemplary Case Cited

Reflects an improvement in the functioning of a computer, or an improvement to other technology or technical field

DDR Holdings, LLC v., L.P., 773 F.3d 1245, 1257-59 (Fed. Cir. 2014)

Applies or uses a judicial exception to effect a particular treatment or prophylaxis for a disease or medical condition

Classen Immunotherapies, Inc. v. Biogen IDEC, 659 F.3d 1057, 1066-68 (Fed. Cir. 2011); Vanda Pharm. Inc. v. West-Ward Pharm. Int’l Ltd., 887 F.3d 1117, 1135 (Fed. Cir. 2018)

Implements a judicial exception with, or uses a judicial exception in conjunction with, a particular machine or manufacture that is integral to the claim

Eibel Process Co. v. Minnesota &

Ontario Paper Co., 261 U.S. 45, 64-65 (1923)

Effects a transformation or reduction of a particular article to a different state or thing

Diamond v. Diehr, 450 U.S. 175, 184 (1981)

Applies or uses the judicial exception in some other meaningful way beyond generally linking the use of the judicial exception to a particular technological environment, such that the claim as a whole is more than a drafting effort designed to monopolize the exception

Diehr, 450 U.S. at 184, 187; see also Finjan Inc. v. Blue Coat Sys., Inc., 879 F.3d 1299 (Fed. Cir. 2018); Core Wireless Licensing, S.A.R.L. v. LG Elecs., Inc., 880 F.3d 1356 (Fed. Cir. 2018)

Examples from the Revised Guidance of circumstances where the judicial exception has not been integrated into a practical application include: 

Additional Element

Exemplary Case Cited

Merely recites the words “apply it” (or an equivalent) with the judicial exception, or merely includes instructions to implement an abstract idea on a computer, or merely uses a computer as a tool to perform an abstract idea

Alice Corp. v. CLS Bank Int’l, 573 U.S. 208, 222-26 (2014); Gottschalk v. Benson, 409 U.S. 63 (1972); Credit Acceptance Corp. v. Westlake Servs., 859 F.3d 1044 (Fed. Cir. 2017)

Adds insignificant extra-solution activity to the judicial exception; or


Mayo Collaborative Servs. v. Prometheus Labs., Inc., 566 U.S. 66, 79 (2012); CyberSource Corp. v. Retail Decisions, Inc., 654 F.3d 1366, 1375 (Fed Cir. 2011); Parker v. Flook, 437 U.S. 584, 590 (1978)

Does no more than generally link the use of a judicial exception to a particular technological environment or field of use

Bilski v. Kappos, 561 U.S. 593, 612 (2010); Flook, 437 U.S. at 588-90

The Revised Guidance further emphasizes that because the revised, two-step approach to step one of Alice/Mayo “does not evaluate whether an additional element is well-understood, routine, conventional activity,” then a claim including “conventional elements may still integrate an exception into a practical application, thereby satisfying the subject matter eligibility requirement of Section 101.”[11]


The Revised Guidance borrows in large part from case law from the pre-Alice/Mayo. For example, the Revised Guidance states that one example of a judicial exception being integrated into a practical application is where the limitation “effects a transformation or reduction of a particular article to a different state or thing”—the quintessential “machine-or-transformation test” inquiry.[12] Yet this category fails to acknowledge the US Supreme Court’s emphasis in Mayo that satisfying the machine-or-transformation test, by itself, is not sufficient to render a claim patent-eligible, as not all transformations or machine implementations infuse an otherwise ineligible claim with an “inventive concept.”[13] While the machine-or-transformation test may continue to provide a “useful clue” as to patent eligibility, it is not determinative.[14]

By taking a categorical approach to what constitutes an “abstract idea” in prong one of the Revised Guidance’s two-prong approach, examiners may find it easier to determine that a limitation recites an abstract idea. As a result, the Revised Guidance should lead to a more even application and predictability across different examiners and art units. If that is the case, practitioners may see the battleground shift to whether the claim as a whole integrates the abstract idea into a practical application of that exception.

Time will tell whether the US Court of Appeals for the Federal Circuit is persuaded by the guidelines and explicitly or implicitly adopts the USPTO’s new framework.[15] More importantly, however, is how long it takes the US Supreme Court to weigh in on any given aspect of the Revised Guidance.

Examining Computer-Implemented Functional Claim Limitations for Compliance with 35 USC 112

The “Computer-Implemented Functional Claim Limitations Guidance” aims to assist USPTO personnel in examining claims “that contain functional language, particularly patent applications where functional language is used to claim computer-implemented inventions.”[16]

First, the Section 112 Guidance addresses examining computer-implemented functional claims having means-plus-function limitations.

Discussing the Federal Circuit’s decision in Williamson v. Citrix Online, LLC, 792 F.3d 1339, 1349 (Fed. Cir. 2015) (en banc), the Revised Guidance recommends that an applicant faced with a USPTO action stating the claim is being interpreted according to Section 112(f) may (1) present a sufficient showing to establish the claim limitation recites sufficient structure to perform the claimed function so as to avoid interpretation under Section 112(f); or (2) amend the claim limitation so as to avoid interpretation under Section 112(f) (e.g., reciting sufficient structure to perform the claimed function).

As to indefiniteness under Section 112(b) for a computer-implemented means-plus-function limitation, it is well established that “the structure disclosed in the specification [must] be more than simply a general purpose computer or microprocessor and that the specification must disclose an algorithm for performing the claimed function.”[17] Absent a disclosed algorithm for performing a computer-implemented means-plus-function limitation, an applicant risks facing a finding of indefiniteness.[18] The requirement cannot be avoided by arguing that one of ordinary skill in the art is capable of writing software to convert a general purpose computer to a special purpose computer to perform the claimed function.[19] Plus, the disclosed algorithm must be sufficient to perform the entire claimed function(s),[20] and ambiguous words in the claim may likewise lead to a determination that a computer-implemented functional claim is indefinite.[21] Finally, the Revised Guidance reminds examiners and applicants alike that a claim found to be indefinite under Section 112(f) will also lack written description under Section 112(a) and may fall short of the enablement requirement under Section 112(a).

Second, the Section 112 Guidance addresses written description and enablement issues for computer-implemented functional claims that recite only the idea of a solution or outcome to a problem without reciting the details of how the solution or outcome is accomplished.

For computer-implemented functional claims, the Section 112 Guidance underscores that whether there is adequate written description support requires examining the sufficiency of both the disclosed hardware and the disclosed software given the interrelationship and interdependence of computer hardware and software.[22]

As to enablement, the Section 112 Guidance explains it “is of particular importance with respect to computer-implemented inventions” that a specification need not disclose what is well known in the art “due to the high level of skill in the art and the similarly high level of predictability in generating programs to achieve an intended result without undue experimentation.”[23] But, an “applicant cannot rely on the knowledge of one skilled in the art to supply information that is required to enable the novel aspect of the claimed invention when the enabling knowledge is in fact not known in the art.”[24]


In large part, the Section 112 Guidance focuses on synthesizing the current standards and case law in the context of computer-implemented functional claims. The standards and case law are nothing new to practitioners. But the emphasis on certain tenants of those standards may signal that particular scrutiny will be paid to computer-implemented functional claims, especially as applicants continually seek to patent next-generation technologies.


If you have any questions or would like more information on the issues discussed in this LawFlash, please contact the authors, Dion M. Bregman in our Silicon Valley office, Karon Fowler in our Chicago office, or any of the following lawyers from Morgan Lewis’s IP disputes team:

Joshua M. Dalton

Century City
Olga Berson, Ph.D.
Andrew V. Devkar
Seth M. Gerber

Michael J. Abernathy
Christopher J. Betti, Ph.D.
Wan-Shon Lo
Krista Vink Venegas, Ph.D.
Jason C. White
Amanda S. Williamson

C. Erik Hawes
David J. Levy
Rick L. Rambo

David W. Marston Jr. 

Louis W. Beardell, Jr.
Kenneth J. Davis
John L. Hemmer
Eric Kraeutler

San Francisco
Brent A. Hawkins
Carla B. Oakley

Silicon Valley
Andrew J. Gray IV
Michael J. Lyons
Yalei Sun

Washington, DC
Natalie A. Bennett
Robert C. Bertin
Eric S. Namrow
Collin W. Park

John V. Gorman

[2] The first step of the Alice/Mayo test is equivalent to Step 2A of the USPTO’s Subject Matter Eligibility Guidance as incorporated into the Manual of Patent Examining Procedure.

[3] Alice Corp. Pty. Ltd. v. CLS Bank Int’l, 573 U.S. 208, 217 (2014).

[4] Revised Guidance at 4.

[5] Id. at 9.

[6] Id. at 26.

[7] Id. at 11, 15, 17, 25.

[8] Id. at 26 n.42.

[9] Id. at 11 n.14.

[10] See id. at 19-21.

[11] Id. at 22.

[12] See Bilski, 545 F.3d at 961-62.

[13] DDR Holdings, LLC v., L.P., 773 F.3d 1245, 1256 (Fed. Cir. 2014) (quoting Mayo, 566 U.S. at 84).

[14] Ultramercial, Inc. v. Hulu, LLC, 772 F.3d 709, 716 (Fed. Cir. 2014).

[15] See Enzo Biochem, Inc. v. Gen-Probe Inc., 323 F.3d 956, 964 (Fed. Cir. 2002) (“The Guidelines, like the Manual of Patent Examining Procedure (‘MPEP’), are not binding on this court, but may be given judicial notice to the extent they do not conflict with the statute.”).

[17] Id. at 10 (quoting Noah Sys., Inc. v. Intuit Inc., 675 F.3d 1302, 1312 (Fed. Cir. 2012)).

[18] Id. at 10-11.

[19] Id. at 12.

[20] Id. at 13.

[21] Id. at 14-15.

[22] Id. at 18-19.

[23] Id. at 20.

[24] Id. at 20.