Table of Contents

Written Description

Narrower claimed ranges are supported by broader disclosed ranges

In RAI Strategic Holdings v. Philip Morris Products, the Federal Circuit, in a 2024 precedential opinion, held that a broader range of a variable in the application as filed provides written description support for a narrower claimed range if the disclosure “reasonably conveys to those skilled in the art that the inventor had possession of the claimed range.” The court looked to whether the broad described range pertains to a different invention than the narrower (and subsumed) claimed range.

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En Banc CAFC reaffirm written description doctrine (03/28/10)

In Ariad Pharmaceuticals et al v. Eli Lilly the CAFC upheld a separate written description requirement. The patent at issue relates to a method for inhibiting an intracellular mechanism for expressing genes driving an immune response. Ariad and its co-plaintiffs sued Eli Lilly for infringement of claims 80, 95, 144, and 145 of the patent. A jury returned a verdict that the claims were valid (meeting the enablement and written description requirments) and infringed. Eli Lilly appealed the Federal Circuit, which reversed the jury's verdict of validity on grounds that the patent fails to set forth an adequate written description in a decision rendered in April 2009 1). The CAFC agreed to rehear en banc to answer the following two questions:

  1. Whether 35 U.S.C. §112, paragraph 1, contains a written description requirement separate from an enablement requirement?
  2. If a separate written description requirement is set forth in the statute, what is the scope and purpose of that requirement?

In answering the first question, the CAFC held that the plain meaning of the statute does not limit the written description requirement solely to requiring enablement. Stated the court: “If Congress had intended enablement to be the sole description requirement of § 112, first paragraph, the statute would have been written differently” and “Finally, a separate requirement to describe one’s invention is basic to patent law. Every patent must describe an invention. It is part of the quid pro quo of a patent. . . .” The CAFC cited the Supreme Court cases Schriber-Schroth 2), Gill v. Wells 3), and Festo 4).

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Fed. Cir. favors PTO on §112 first paragraph rejection (07/08/07)

In rejecting a claim, the examiner must set forth express findings of fact which support the lack of written description conclusion. . . . These findings should . . . (B) Establish a prima facie case by providing reasons why a person skilled in the art . . . would not have recognized that the inventor was in possession of the invention as claimed. . . . A simple statement such as “Applicant has not pointed out where the new (or amended) claim is supported, nor does there appear to be a written description of the claim limitation ___ in the application as filed.” may be sufficient where the claim is a new or amended claim, the support for the limitation is not apparent, and applicant has not pointed out where the limitation is supported.*

In Hyatt v. Dudas, the Fed. Cir. reversed the lower court's ruling that the PTO failed to make out a prima facie rejection under 35 U.S.C. §112, first paragraph. During prosecution of a continuation application with a family lineage going back decades, Hyatt withdrew all pending claims and submitted 1,100 new claims directed to various combinations of disclosed elements. The examiner initially rejected a representative sample of the claims for failing the written description requirement because while each individual element was disclosed in that specification, nowhere did Hyatt specify the particular configurations or combinations of elements claimed. The Fed. Cir. reversed holding “that § 2163.04(I)(B) [of the MPEP] as written is a lawful formulation of the prima facie standard for a lack of written description rejection.”

1)
Ariad, 560 F.3d at 1369
2)
Schriber-Schroth Co. v. Cleveland Trust Co., 305 U.S. 47 (1938)
3)
89 U.S. (22 Wall.) 1 (1874)
4)
Festo Corp. v. Shoketsu Kinzoku Kogyo Kabushiki Co., 535 U.S. 722, 736 (2002)