The USPTO’s New Guidelines on Prophetic and Working Examples in Patent Applications and Corresponding Practices in India and China

“Though these new guidelines may seem unnecessary, there is clear benefit to the public, especially to the applicants who rely on patents for future innovative endeavors.” United States Patent and Trademark Office (USPTO) publishes a large number of notices in addition to guidelines for patent applicants. These guidelines are frequently updated, and it is critical to stay informed of those updates. On July 1, 2021, the USPTO published a notice in the Federal Register titled “Properly Presenting Prophetic and Working Examples in a Patent Publication.” In this notice, the USPTO defined prophetic and working examples, distinguished these concepts, and described their use and importance within patent applications. In contrast, this distinction is not made under Indian or Chinese law or practice. Furthermore, applicants are generally not required to provide prophetic or working examples, and the concept of prophetic examples is not recognized under Indian or Chinese patent law.

For a U.S. patent application to be considered complete, it must include a written description of the invention and an example of the invention’s use. The exception would be a case where it is straightforward for someone in a field relevant to the patent to make and use the invention. Any required example may be either prophetic or working. A prophetic example, also known as a paper example, does not require proven results. It has been laid out entirely on paper but has not yet been tested. These examples would describe the expected results, but experimentation to achieve those expected results has not been performed. On the other hand, working examples are based upon experimentation, in which the results were successful. To clarify, we will symbolize the contrast in these examples using a cake. If an inventor has baked the cake and has it ready on a plate, a description of this would be considered a working example. If the inventor has written a recipe for that specific cake with detailed steps, but the cake has never been made, this would be a prophetic example. In general, blueprints, plans, and drawings are often equated with prophetic examples, while descriptions of man-made biotech and chemical compounds, working prototypes, completed projects, and tested software would be considered working examples.

The legitimacy of a prophetic example is equal to that of a working example, provided the wording used in the application is correct. The notice includes a subsection restating the importance of the “Applicant’s Duty of Disclosure.” The USPTO emphasizes that the applicant must be careful not to submit any false or inaccurate data, information, evidence, or statements. Using the wrong tense to describe a prophetic example would deem a submission incorrect. A prophetic example can only use present or future tense. Using past tense is improper because it implies the experiment has finished, which is not the case for a prophetic example. Though the Manual of Patent Examining Procedure of the USPTO states that an application does not need working examples and can use prophetic examples instead, prophetic examples have more guidelines due to the results being purely theoretical. The validity of a prophetic example can be called into question when the example is described with aspects of vagueness. Detailed descriptions and thorough explanations are necessary to qualify a prophetic example. Furthermore, if the hypothetical results of a prophetic example are referred to as actual results, even in the slightest manner, that example, along with the entire application, can be called into question. Clarifying that the example is prophetic is extremely important in a patent application. Fortunately, for applicants using detailed and clear prophetic examples, the example does not have to prove that an invention works completely. If the success of the example is reasonable enough, it will be considered equal to an example with experimented success. The exact words in the notice are, “A patent application does not need to provide a guarantee that a prophetic example actually works. … Only a sufficient description enabling a person of ordinary skill in the art to carry out an invention is needed.” In short, if the example is detailed enough that a non-expert can use the invention, it is not necessary to verify the results. Should the application be rejected on the grounds of ambiguity of prophetic examples or clarification of the type of example, the applicant can respond to the rejection with either the results of an actual test, or a proper rebuttal as to why a prophetic example’s assumptions are reasonable.

The lengthy notice may be boiled down to a few takeaways:

  1. Prophetic examples, also called paper examples, are typically used in a patent application to describe reasonably expected future or anticipated results.
  2. Clarification between prophetic and working examples is key. Both types of examples are valid and equal, but they must be specified as to their respective type.
  3. A patent application does not need to provide a guarantee that a prophetic example is effective.
  4. Prophetic examples must use the correct tense, whether that be present or future tense.
  5. Prophetic examples should not be described using the past tense. Past tense can only be used for working examples that have proven past results.
  6. Readers should be able to readily distinguish between actual results and predicted results.
  7. Do not leave any room for confusion between the examples. Results must not be labeled or referred to as real unless the results have been achieved. Any misleading information is grounds for rejection of the application and invalidation of the patent.
  8. When prophetic examples are described in a manner that is ambiguous or that implies the results are actual, the adequacy and accuracy of the disclosure may come into question.

The notice concludes by referring to the ways that the distinction between prophetic and working examples will “enhance the public’s ability to rely on the patent disclosure.” Though these new guidelines may seem unnecessary, there is clear benefit to the public, especially to the applicants who rely on patents for future innovative endeavors.

Position in India

In India, the contents of the specification are defined under Section 10 of the Patents Act,1970. Additionally, Form-2 prescribes a preamble to the provisional and complete specifications. Regarding complete or non-provisional specifications, it states that “the following specification particularly describes the invention and the manner in which it is to be performed.” Therefore, the preamble to the specification clarifies that the applicant must not only describe the invention in particular but must also express the manner in which the invention will be performed. Although this preamble does not clearly require the applicant to provide an example in the specification, it implies that an illustrative example could be one way of describing the manner in which the invention is to be performed. In fact, one of the objectives of this description or disclosure of the invention by the applicant is to enable the person skilled in the art to perform the invention across the entire span of the claimed invention. Hence, a single example of a method of performing the invention in the complete specification may be sufficient to facilitate or enable a person skilled in the art to work the invention.

In addition, Section 10 of the Patents Act,1970 provides detailed requirements regarding the content of the specification. Section 10(4)(a) states, “Every complete specification shall fully and particularly describe the invention and its operation or use and the method by which it is to be performed.” Further, Section 10(4)(b) provides that complete specification shall “disclose the best method of performing the invention which is known to the applicant and for which he is entitled to claim protection.” This could be substantiated or supplemented by accompanying drawings, models or a sample of anything illustrating the invention. Although Section 10 does not specifically require it, the wording referring to best methods of performing the invention to enable a person skilled in the art to repeat the invention without undue experimentation would clearly indicate working examples are recommended.

The Manual of Patent Office Practice and Procedure of the Indian Patent Office, Version 3.0, paragraph 05.03.09, states, “Description of an invention is required to be furnished in sufficient detail so as to give a complete picture of the invention and follows the Summary of invention.” It further states, “The nature of improvements or modifications effected with respect to the prior art should be clearly and sufficiently described. In addition, it states, “It may include examples/drawings or both for clearly describing and ascertaining the nature of the invention. Examples must be included in the description, especially in the case of chemical related inventions.”

Further, the “Guidelines for examination of patent applications in the field of pharmaceuticals” page No. 39, para 11.6 maintains that “the description in the specification should contain at least one example or more than one example, covering the full breadth of the invention as claimed, which enable(s) the person skilled in the art to carry out the invention. If the invention is related to product per se, description shall be supported with examples for all the compounds claimed or at least all the genus of the compounds claimed. Method for preparation and experimental data relating to properties of representatives of each embodiment claimed shall be incorporated in the description, which enable a person having ordinary skilled in the art can make use of the invention without undue burden”.

Position in China

There are several laws, guidelines and regulations governing patent applications in the People’s Republic of China (“PRC”) namely the Patent Law of the People’s Republic of China, Rules for the Implementation of the Patent Law of the People’s Republic of China, and Guidelines for Patent Examination. However, unlike the laws, guidelines, and regulations for patent applications in the United States, which are comprehensive and provide detailed specifications on how a patent application description should be presented, the laws, guidelines and regulations in the PRC do not provide details or specific requirements on patent application descriptions. Instead, they merely provide that patent applications will be rejected if there is insufficient disclosure by the applicant, but the degree of disclosure required is not expressly stated. For patent applications in the PRC, the patent examiner will usually focus on three principal criteria: practicality, novelty, and creativity. Although the patent examiner may consider other criteria in addition to these three principal criteria, these other criteria are usually deemed to be less significant and may not be taken into consideration in the examination process.

Premised on the above, the new guidelines introduced by the USPTO in relation to prophetic and working examples in patent applications is not expected to have significant impact on the patent application in the PRC. In general, patent examiners in the PRC do not place great emphasis on the workability of the details provided in the patent description, as there is no requirement for the patent applicants to prove that the data, information, evidence, or statement, provided they have been experimented upon and successfully proven. Under the new USPTO guidelines, patent applicants may need to distinguish the use of past, present, or future tense in their patent application description to differentiate between prophetic examples and working examples. However, patent applicants in the PRC need not worry about this because (1) there is no requirement under the laws, guidelines, and regulations of the PRC for the patent applicants to differentiate between prophetic examples and working examples in their patent application description; and (2) all patent applications in the PRC require drafting and submission in Mandarin which, unlike the English language, has no distinction between past, present, and future tense.

Time for Change

Neither Indian nor the PRC patent law specifically prescribe the requirement of inclusion of working or prophetic examples and do not place much emphasis on this concept. However, there is ample indication that inclusion of examples wherever possible to meet the requirement of disclosing the best method of performing the invention so as to enable the person skilled in the art to repeat the invention without undue experimentation is recommended. Having at least one example in the specification has been a practice in India, like that in the United States, particularly in the case of chemical or pharmaceutical related inventions to facilitate the person skilled in the art to perform the invention and its working in order to meet the sufficiency of the description requirement. The requirement relating to pharmaceutical or chemical inventions is equally applicable in India and the United States, i.e., applicants must illustrate the invention with the inclusion of one or more working examples.

Considering the evolution of the patent system in India over the last decade particularly patent litigation on the grounds of insufficiency of disclosure or description, it is high time for change. The Indian patent law needs to be amended to prescribe the requirement of inclusion of at least one example, whether working or prophetic, wherever possible. Facilitating the performance of the invention by a person skilled in the art with the directions given in that example to meet the requirement of sufficiency of description would mitigate, if not avoid, litigation on this ground. This practice of requiring at least one working or prophetic example will also help the applicants and patent examiners expedite the process of examination.

In the PRC, patent examiners are mainly concerned with the three main criteria – practicality, novelty, and creativity of the patent application while other criteria such as prophetic and working examples may or may not be taken into consideration by the patent examiner. In an instance of patent applications involving products – such as healthcare (medicine and medical treatment) and engineering solutions requiring proof that they work, our stance is that lawmakers in the PRC should consider revising the relevant laws, guidelines, and regulations to add consideration of prophetic and working examples in patent examination to enable patent examiners to distinguish between patents proven to work from those still in the theoretical stage.

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Join the Discussion

4 comments so far.

  • [Avatar for Anon]
    November 19, 2021 08:48 am


    There is no doubt that you believe what you say — just as those on Peak Stupid do.

    I’m not going to comment about patents in gields I am not an expert in.

    And yet, you do.

  • [Avatar for Benny]
    November 19, 2021 08:10 am

    In my “field of expertise” I have been granted 6 US patents. I know a thing or two about it. I’m not going to comment about patents in gields I am not an expert in.
    I have misplaced nothing, I recognize full well when reducing a patent specigication to practice would require undue experimentation, and hundreds if not thousands of hours work by the R&D team.

  • [Avatar for Anon]
    November 18, 2021 01:56 pm

    Well Benny, from what I have seen of your posted positions, the fact that you would classify anything pertaining to yourself with “own field of expertise” reminds me of a certain false confidence chart that appeared on this blog recently.

    (you also seemed to have misplaced the part about “without undue experimentation”)

  • [Avatar for Benny]
    November 18, 2021 12:50 pm

    “a sufficient description enabling a person of ordinary skill in the art to carry out an invention is needed.”

    I’ve lost count of the number of granted patents in my own field of expertise that I’ve read which don’t meet this requirement. All too often the claim includes something like “a processor configured to perform a miracle”.