According to U.S. patent law, the specification of a patent application must adequately describe, enable, and provide the best mode for carrying out an invention as required by 35 U.S.C. § 112(a) which states:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
Thus, § 112(a) requires that a specification include the following:
(a) a written description of the invention;
(b) the manner and process of making the invention (the enablement requirement); and
(c) the best mode contemplated by the inventor for carrying out the invention.
The written description requirement is separate and distinct from the enablement requirement.
This five-part series will provide an in-depth examination of the written description requirement. Part one will describe the basics of the written description requirement. Part two will examine several seminal Federal Circuit decisions that have been decided over the course of time involving written description. Part three will examine written description issues relating to the patenting of antibodies. Part four will review several decisions by the Federal Circuit involving written description during this past year (2019). Part five will provide tips and strategies for navigating, avoiding and overcoming written description issues, particularly with respect to life science inventions.
Basics of Written Description
The main goals of the written description requirement are to: (1) clearly convey the information that the applicant has invented the subject matter which is claimed; (2) convey to the public what the applicant claims as the invention; and (3) promote the progress of science and the useful arts by ensuring that the patentee adequately describes its invention in exchange for the right to exclude others from practicing the invention during the duration of the patent’s term.
To satisfy the written description requirement, the specification must describe the claimed invention in sufficient detail such that a person of ordinary skill in the art (POSITA) can reasonably conclude that the inventor had possession of the claimed invention. Specifically, the objective standard for determining compliance with the written description requirement involves determining whether the specification clearly allows a POSITA to recognize that the inventor had “possession of” the claimed invention at the time of filing (e.g., earliest priority date). For example, the claimed invention may not be adequately described if the claims require an essential or critical feature which is not adequately described in the specification or which is not known or conventional in the art.
An applicant can show possession of the claimed invention in a variety of ways, such as by: (1) describing the claimed invention with all of its limitations using descriptive means such as words, structures, amino acid and/or nucleic acid sequences, figures, diagrams, and formulas that fully set forth the claimed invention; (2) including a description of an actual reduction to practice; (3) showing that the invention was “ready for patenting” such as by the disclosure of drawings or structural chemical formulas demonstrating that the invention was complete; and/or (4) describing distinguishing identifying characteristics of the claimed invention compared to other materials.
Compliance with the written description requirement is a question of fact which must be resolved on a case-by-case basis. The specification as filed is presumed to be adequate unless an examiner provides sufficient evidence or reasoning to the contrary to rebut the presumption.
It is important to recognize that the written description requirement is not necessarily met just because the claim language appears ipsis verbis in the specification. As the Federal Circuit stated in Enzo Biochem, Inc. v. Gen-Probe, Inc., “[E]ven if a claim is supported by the specification, the language of the specification, to the extent possible, must describe the claimed invention so that one skilled in the art can recognize what is claimed. The appearance of mere indistinct words in a specification or a claim, even an original claim, does not necessarily satisfy that requirement.”
Questions as to whether the specification provides an adequate written description may arise in the context of determining (1) whether an original claim was described sufficiently; (2) whether new or amended claims are supported by the description of the invention in the application as filed; or (3) whether a claimed invention is entitled to the benefit of an earlier priority date or effective filing date under 35 U.S.C. § 119, 120, 365 or 386.
Although there is a presumption that an adequate written description of a claimed invention is present in the specification at the time of filing, problems often arise when (1) the claims define the invention using functional language specifying the desired result but the specification fails to sufficiently identify how the function is performed or the result is achieved; or (2) broad genus claims are presented but the specification only describes a narrow species with no evidence that the genus is contemplated. With respect to claiming a genus, the written description requirement can be satisfied through a sufficient description of a representative number of species. A “representative number of species” means that the species which are described are representative of the entire genus. Thus, when there is substantial variation within the genus, an applicant must describe a sufficient variety of species to reflect the variation within the genus. Unfortunately, neither the USPTO nor the courts have provided any helpful guidance on how many species must be described to constitute a “representative” number to support a genus claim.
With respect to new claims, amended claims, or claims asserting entitlement to priority under 35 U.S.C. § 119, 120, 365 or 386, as mentioned previously, the examiner has the initial burden of presenting evidence or reasoning to explain why a person skilled in the art would not recognize, in the original specification, a description of the invention as defined by the claims. To comply with the written description requirement under § 112(a) or to be entitled to an earlier priority date or filing date under §§ 119, 120, 365 or 386, each claim limitation must be expressly, implicitly, or inherently supported in the originally filed specification. When an explicit limitation in a claim “is not present in the written description whose benefit is sought it must be shown that a person of ordinary skill would have understood, at the time the patent application was filed, that the description requires that limitation.” If the originally filed specification does not provide support for each claim limitation, or if an element which the applicant describes as essential or critical is not claimed, a new or amended claim will likely be rejected under § 112(a) as lacking adequate written description, or in the case of priority or benefit claim under §§ 119, 120, 365 or 386, the priority claim will likely be denied.
An applicant can respond to a § 112(a) written description rejection by: (1) identifying the relevant portion of the specification that provides written description support for the claims; (2) amending the claims; (3) submitting a declaration or affidavit by an expert explaining why one skilled in the art would understand that the inventors were in possession of the claimed subject matter at the time of the filing date of the application; and (4) any combinations of (1)-(3).
In our next post, we will examine some of the seminal Federal Circuit decisions that have issued over the course of time involving written description.
- In re Barker, 559 F.2d 588, 592 n. 4 (CCPA 1977).
- Regents of the Univ. of Cal. v. Eli Lilly, 119 F.3d 1559, 1566 (Fed. Cir. 1997), cert. denied, 523 U.S. 1089 (1998).
- MPEP chapter 2163 Rev. 08. 2017, January 2018
- See Lockwood v. Amer. Airlines, Inc., 107 F.3d 1565, 1572 (Fed. Cir. 1997); Pfaff v. Wells Elecs., Inc., 525 U.S. 55, 68 (1998); Regents of the Univ. of Cal., 119 F.3d at 1568 (Fed. Cir. 1997), cert. denied, 523 U.S. 1089 (1998).
- In re Marzocchi, 439 F.2d 220, 224 (CCPA 1971).
- Enzo Biochem, Inc. v. Gen-Probe, Inc., 323 F.3d 956, 968 (Fed. Cir. 2002).
- 35 U.S.C. § 132 provides that no amendment shall introduce new matter into the specification.
- Ariad Pharm., Inc. v. Eli Lilly and Co., 598 F.3d 1336, 1349-50 (Fed. Cir. 2010) (en banc).
- See AbbVie Deutschland GmbH & Co., KG v. Janssen Biotech, Inc., 759 F.3d 1285, 1300 (Fed. Cir. 2014).
- Hyatt v. Boone, 146 F.3d 1348, 1353 (Fed. Cir. 1998).