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Proposed Software Patent Examination Guidelines

This document contains the guidelines originally proposed for the examination of Computer-Implemented Inventions, as well as the legal analysis by the U.S. Patent and Trademark Office to support the proposed examination guidelines. These guidelines have been finalized. The final guidelines can be found in BitLaw. This document is divided into three parts, with each part being taken directly from the materials provided at the U.S.P.T.O. ftp site:

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Legal Analysis to Support Proposed Examination

Guidelines for Computer-Implemented Inventions

October 3, 1995

Patent and Trademark Office

United States Department of Commerce


I. Introduction [Guidelines § I.A.]

II. Determine What Applicant Has Invented and Is Seeking to Patent [Guidelines § I.B.1.]
 A. Identify and Understand the Practical Utility Asserted for the Invention [Guidelines § I.B.1.(a)]
 B. Review the Detailed Disclosure and Specific Embodiments of the Invention to Determine What the Applicant Has Invented [Guidelines § I.B.1.(a)]
 C. Analyze the Claims [Guidelines § I.B.1.(b)]

III. Assess Claimed Invention for Compliance with 35 U.S.C. § 101 [Guidelines § I.B.1.(c)]
 A. Determine Whether The Invention is "Useful"
 B. Classify the Invention as to Its Proper Statutory Category
  1. Non-Statutory Subject Matter [Guidelines § I.B.1.(c)(i) & (ii)]
   (a) "Data Structures" Per Se or Computer Programs Per Se
   (b) Non-Functional Information
   (c) Natural Phenomena Such as Electricity and Magnetism
  2. Statutory Subject Matter
   (a) Statutory Products
    (i) Product Claims--Claims Directed to Machines and Manufactures
    (ii) Claims that Encompass Any Machine or Manufacture Embodiment of a Process
   (b) Statutory Processes [Guidelines § I.B.1.(c)(iii)]
    (i) Appropriate Subject Matter for Manipulation Steps of a Process
    (ii) Transformation or Reduction to a Different State or Thing
    (iii)Examples of Statutory Computer-Implemented Processes
  3. Non-Statutory Processes
   (a) Mathematical Algorithm That Defines a Law of Nature or Natural Phenomenon or Describes an Abstract Idea
   (b) Evaluation of Certain Language Related to Mathematical Operation Steps of a Process
    (i) Intended Use or Field of Use Statements
    (ii) Necessary Antecedent Step to Performance of a Mathematical Operation or Independent Limitation on a Claimed Process
    (iii)Post-Mathematical Operation Step Uses Solution or Merely Conveys Result of Operation
   (c) Manipulation of Abstract Ideas Without a Practical Application

IV. Issues Related to Compliance with Section 112, First and Second Paragraphs [Guidelines § I.B.2.]
 A. Specification Fails to Show How to Make or Use Programmed Computer Element of Invention [Guidelines § I.B.2.(b)]
 B. Programmed Computer Is Defined As Composite of Functional Elements
 C. Elements of a Machine Defined Using Means Plus Function Language [Guidelines § I.B.2.(a) & (b)]
 D. Claim Does Not Define Applicant's Invention [Guidelines § I.B.2.(a)]
 E. Claim Defined Using Only Computer Program Code [Guidelines § I.B.2.(a)]

V. Issues Related to Compliance with § 103 [Guidelines § I.B.3.]

VI. Conclusion

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I. Introduction [Guidelines § I.A.]

The Office has developed Proposed Examination Guidelines for Computer-Implemented Inventions and this legal analysis (collectively, the "guidelines") to assist Office personnel in the examination of applications drawn to computer-implemented inventions. The guidelines are based on the Office's current understanding of the law, and represent the official policy of the Patent and Trademark Office. Office personnel are to rely on these guidelines in the event of any inconsistent treatment of issues between these guidelines and any earlier provided guidance from the Office.

The guidelines alter the procedures Office personnel shall employ to examine applications drawn to computer-implemented inventions. The guidelines also clarify the Office's position on certain patentability standards related to this field of technology. The positions set forth in these guidelines are believed to be fully consistent with the binding precedent of the Supreme Court, and the Federal Circuit and its predecessor courts.

The Freeman-Walter-Abele test, while of limited value, may still be relied upon in analyzing claims directed solely to a process for solving a mathematical algorithm. "Business methods" are to be analyzed the same way as any other process.

The appendix includes the proposed guidelines and a graphic overview of how Office personnel will conduct an examination to determine statutory subject matter.

II. Determine What Applicant Has Invented and Is Seeking to Patent [Guidelines § I.B.1.]

It is essential that patent applicants obtain a prompt yet complete examination of their applications. Thus, Office personnel must raise any issue that may affect patentability in the initial action on the merits. Under the principles of compact prosecution, each claim should be reviewed for compliance with every statutory requirement of patentability in the initial review of the application, even if one or more claims is found to be deficient with respect to one statutory requirement. Deficiencies should be explained clearly, particularly when they serve as a basis for a rejection. Where possible, Office personnel should indicate how rejections may be overcome and problems resolved. A failure to follow this approach can lead to unnecessary delays in the prosecution of the application.

Prior to focusing on any specific statutory requirements, Office personnel must begin examination by determining what, precisely, the applicant has invented and is seeking to patent, and how the claims relate to and define that invention. Consequently, Office personnel will no longer begin examination by determining if a claim recites a "mathematical algorithm." Rather, they will review the complete specification, including the detailed description of the invention, any specific embodiments that have been disclosed, the claims and the specific utility that has been asserted for the invention.

A. Identify and Understand the Practical Utility Asserted for the Invention [Guidelines § I.B.1.(a)]

The subject matter sought to be patented must be a "useful" process, machine, manufacture or composition of matter. Accordingly, a complete disclosure should contain some indication of why the applicant believes the claimed invention is "useful." This "usefulness" of the invention is called the "specific" or "practical" utility of the invention. Specific or practical utility is simply a shorthand way of attributing "real world" value to the claimed subject matter, i.e., assuring there is some benefit to the public. An invention that has some practical application satisfies the utility requirement.

The applicant is in the best position to explain why an invention is believed useful. Office personnel should therefore focus their efforts on identifying statements made in the specification that identify a practical application for the invention. Office personnel should rely on such statements throughout the examination when assessing the invention for compliance with all statutory criteria. Deficiencies under the utility requirement will be rare, however. Further guidance in evaluating an asserted specific utility for compliance with § 101 is provided below and in the Utility Examination Guidelines.If the applicant asserts a practical utility for the invention, Office personnel should review the entire disclosure to determine the features necessary to accomplish the asserted practical utility.

B. Review the Detailed Disclosure and Specific Embodiments of the Invention to Determine What the Applicant Has Invented [Guidelines § I.B.1(a)]

The written description will provide the clearest explanation of the applicant's invention, by exemplifying the invention, explaining how it relates to the prior art and by explaining the relative significance of various features of the invention. Accordingly, Office personnel should begin their evaluation of a computer-implemented invention as follows:

- determine what the programmed computer does when it performs the processes dictated by the software (i.e., the functionality of the programmed computer);

- determine how the computer is to be configured to provide that functionality (i.e., what elements constitute the programmed computer and how are those elements to be configured to provide the specified functionality); and

- if applicable, determine the relationship of the programmed computer to other subject matter that constitutes the invention (e.g., machines, devices, materials, or process steps other than those that are part of or performed by the programmed computer).

Patent applicants can assist the Office by preparing applications that clearly set forth these aspects of a computer-implemented invention.

C. Analyze the Claims [Guidelines § I.B.1.(b)]

The claims define the property rights provided by a patent, and thus require careful scrutiny. The goal of claim analysis is to identify the boundaries of the protection sought by the applicant and to understand how the claims relate to and define what the applicant has indicated is the invention. Office personnel must analyze the language of a claim before determining if the claim complies with each statutory requirement for patentability.

Office personnel should begin claim analysis by identifying and evaluating each claim element. For processes, the claim elements will define steps or acts to be performed. For products, i.e., machines and articles of manufacture, the claim elements will define discrete physical structures. The discrete physical structures may be comprised of hardware or a combination of hardware and software.

As provided in the guidelines, Office personnel are to correlate each claim element to that portion of the disclosure that describes the claim element. This is to be done in all cases, i.e., whether or not the claimed invention is defined using means or step plus function language. The correlation step will ensure that Office personnel clearly understand the meaning and scope of each claim limitation.

The subject matter of a properly construed claim is defined by the terms that limit its scope, and it is this subject matter that must be examined. As a general matter, the grammar and intended meaning of terms used in a claim will dictate whether the language limits the claim scope. Language that suggests or makes optional but does not require steps to be performed or does not limit a claim to a particular structure does not limit the scope of a claim or claim element.

Office personnel must rely on the applicant's disclosure to properly determine the meaning of terms used in the claims. An applicant is entitled to be his or her own lexicographer, and in many instances will provide an explicit definition for certain terms used in the claims. Where an explicit definition is provided by the applicant for a term, that definition will control interpretation of the term as it is used in the claim. Office personnel should determine if the original disclosure provides a definition consistent with the applicant's assertions. If the applicant asserts that a term has a meaning that conflicts with the term's art-accepted meaning, Office personnel should encourage the applicant to amend the claim to better reflect what applicant intends to claim as the invention.

Office personnel are to give claims their broadest reasonable interpretation in light of the supporting disclosure. With the exception of claim elements defined in means or step plus function terminology, positive limitations on the scope of a claim cannot be read into the claims based on comments or explanations provided in the disclosure. While it is appropriate to use the specification to determine what applicant intended a term to mean, a positive limitation from the specification cannot be read into a claim that does not impose that limitation. A broad interpretation of the claims by the Office will reduce the possibility that the claim, when issued, will be interpreted more broadly than is justified or intended. An applicant always has the opportunity to amend the claims during prosecution to better reflect the intended scope of the claim.

Finally, when evaluating the scope of a claim, every limitation in the claim must be considered. Office personnel may not dissect a claimed invention into discrete elements and then evaluate the elements in isolation. Instead, each claimed element of the invention must be considered in the context of the claim as a whole.

III. Assess Claimed Invention for Compliance with 35 U.S.C. § 101 [Guidelines § I.B.1.(c)]

As the Supreme Court has held, Congress chose the expansive language of § 101 so as to include "anything under the sun that is made by man." Accordingly, § 101 of title 35, United States Code, provides:

Whoever invents or discovers any new and useful process, machine, manufacture, or composition of matter, or any new and useful improvement thereof, may obtain a patent therefor, subject to the conditions and requirements of this title.

As cast, § 101 defines four categories of inventions that Congress deemed to be the appropriate subject matter of a patent; namely, processes, machines, manufactures or compositions of matter. The latter three categories define "things" while the process category defines inventions that consist of "actions" (i.e., a series of steps or acts to be performed).

Federal courts have held that § 101 does have certain limits. First, the phrase "anything under the sun that is made by man" is limited by the text of § 101, meaning that one may only patent something that is a machine, manufacture, composition of matter or a process. Second, § 101 requires that the subject matter sought to be patented be a "useful" invention. Accordingly, a complete definition of the scope of § 101, reflecting Congressional intent, is that any new and useful process, machine, manufacture or composition of matter under the sun that is made by man is the proper subject matter of a patent. Subject matter not within one of the four statutory invention categories or which is not "useful" in a patent sense, accordingly, is not eligible to and cannot be patented.

The subject matter courts have found to be outside the four statutory categories of invention is limited to abstract ideas, laws of nature and natural phenomena. While this is easily stated, determining whether an applicant is seeking to patent an abstract idea, a law of nature or a natural phenomenon has proven to be challenging. These three exclusions recognize that subject matter that is not a practical application or use of an idea, a law of nature or a natural phenomenon is not patentable.

Courts have expressed a concern over "preemption" of ideas, law of natures or natural phenomena. The concern over preemption serves to bolster and justify the prohibition against the patenting of such subject matter. Such concerns are only relevant to claiming a scientific truth or principle. Thus, a claim to an "abstract" idea is non-statutory because it does not represent a practical application of the idea, not because it would preempt the idea.

A. Determine Whether The Invention is "Useful"

To be patentable, an invention must be "useful" (i.e., it must have a practical application). The purpose of this requirement is to limit patent protection to inventions that possess a certain level of "real world" value, as opposed to subject matter that represents nothing more than an idea or concept, or is simply a starting point for future investigation or research. The utility of an invention must be within the "technological" arts. This requirement can be discerned from the variously phrased prohibitions against the patenting of abstract ideas, laws of nature or natural phenomenon. Courts have indicated that any technological or utilitarian purpose may serve as an appropriate utility.

Office personnel should confirm that the utility asserted for an invention is a practical application of the invention. If the utility of an "invention" is only as an object of philosophical inquiry or to be appreciated in terms of its literary or artistic value, the claimed invention should be rejected under § 101.

Additionally, Office personnel have struggled with claims directed to methods of doing business. A method of doing business is to be treated like any other process.

B. Classify the Invention as to Its Proper Statutory Category

To properly assess compliance with the statutory invention requirements of § 101, Office personnel should classify each specifically claimed invention into one statutory or non-statutory category. If the subject matter falls into a non-statutory category, that should not preclude complete examination of the application for all other conditions of patentability. This classification is only an initial finding at this point in the examination process that will be again assessed after the examination for compliance with §§ 112, 102 and 103 and before issuance of any Office action.

1. Non-Statutory Subject Matter [Guidelines § I.B.1.(c)(i) & (ii)]

Claims that are clearly non-statutory are those that define:

-- a "data structure" per se or computer program per se, i.e., information rather than a computer-implemented process or specific machine or computer readable memory manufacture;

-- a compilation or arrangement of non-functional information or a known machine-readable storage medium that is encoded with such information;

-- natural phenomena such as electricity and magnetism.

Claims in this form are indistinguishable from abstract ideas, laws of nature and natural phenomena and may not be patented. Claims to processes that do nothing more than solve mathematical problems or manipulate abstract ideas or concepts are more complex to analyze and are addressed below. See section 3.

(a) "Data Structures" Per Se or Computer Programs Per Se

Computers manage data by arranging the data in a particular order or sequence. The relationship that exists among the ordered data elements (i.e., the individual facts or data) is called a "data structure." Data structures in this sense are not statutory products because they are not physical "things" nor are they statutory processes, as they are not "acts" being performed. In other words, when defined without any physical structure, a "data structure" is nothing more than information that explains a relationship that exists among ordered data, and therefore is non-statutory. In contrast, a memory circuit whose structure represents a practical application or use of a data structure is a statutory manufacture. Accordingly, it is important to distinguish claims that define information per se from claims that define statutory inventions that are based on or use non-statutory information.

Similarly, computer programs per se are not physical "things," nor are they statutory processes, as they are not "acts" being performed. In contrast, a computer process that is implemented using a computer program, a specific computer reconfigured by a computer program, or a memory circuit whose structure is defined by a computer program are statutory.

If a computer program is recited in a claim, Office personnel should determine if the computer program is being used to describe the physical structure of a manufacture or machine, or steps to be performed by a computer, or is intended to be the object of the patent, per se.

If it is clear that the claim uses the computer program elements to define actions to be performed by a computer, Office personnel should treat the claim as a process claim. If the computer program elements are recited in conjunction with a physical structure, such as a computer memory, the claim should be treated as a product claim. If the claimed subject matter cannot be treated as a process and does not have any physical structure, then it is non-statutory "information."

If an applicant challenges the Office's classification of a claim containing computer program elements without any physical structure as a process rather than a product, the claim should be rejected under § 101. Office personnel should also object to the specification under 37 CFR 1.71(b) if such an assertion is made, as the complete invention contemplated by the applicant has not been cast precisely as being an invention within one of the statutory categories.

(b) Non-Functional Information

The term "information" is the "communication of data." It is also used to mean signals representing data. It is the latter definition that is used in these guidelines.

Certain information, such as music, literature, art, and photographs, as well as mere facts or data, cannot impart functionality to a computer. Such "information" is not a process, machine, manufacture or composition of matter.

The policy that precludes the patenting of non-functional data would be easily frustrated if the same data could be patented as an article of manufacture. For example, music is commonly sold to consumers in the format of a compact disc. In such cases, the known compact disc acts as nothing more than a carrier for non-functional data.

The non-functional content (e.g., words, images, or other information) cannot provide the practical utility for the manufacture. Function-imparting information is necessary to create a functional and useful physical manufacture (e.g., a computer memory encoded with data that causes a computer to function in a particular manner). If the utility for the encoded medium is dependent upon a human appreciating the artistic or other value of the information content, the claimed invention should be rejected under § 101.

(c) Natural Phenomena Such as Electricity and Magnetism

Claims that recite nothing but the physical characteristics of a form of energy, such as a specific radio frequency, voltage, or the strength of a magnetic field, define energy or magnetism, per se, and as such are non-statutory. A claim directed to a natural phenomenon such as energy or magnetism, which does not recite the practical application of that phenomenon in a process or a product, is to be rejected under § 101.

2. Statutory Subject Matter

(a) Statutory Products

If a claim defines a useful machine or manufacture by identifying the physical structure of the machine or manufacture in terms of its hardware or hardware and software combination, it defines a statutory product.