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How to Prepare a Patent Specification to Maximize the Protection of Computer-Implemented Inventions


HOW IS 35 U.S.C § 112, ¶ 6 USED


Although the scope of a patent claim for infringement and validity purposes depends in the first analysis on the language of the claim itself, it is the written description that gives meaning to the claim language. In other words, a claim is construed in light of, and the proper scope of a claim depends upon, the written description supporting that claim. Thus, determinations of infringement, whether literal or under the Doctrine of Equivalents, determinations of whether the claimed invention is statutory under 35 U.S.C. § 101, and determinations of whether the claimed invention is anticipated or obvious under 35 U.S.C. §§ 102 and 103 all depend fundamentally upon how the patent scrivener prepares the written disclosure.

The completeness and extent of the invention description raises conflicting issues. On one side are the requirements of 35 U.S.C. § 112, ¶ 1 that patent specifications set out both an enabling embodiment of the invention and the best mode of practicing the invention. On the other side rests the question of how broad is the scope of a claim supported by a given specification. The commercial worth of a patent depends upon the scope of its claims for determining whether a competitor's products or processes infringe those claims. The scope of a claim for infringement purposes, as well as for issues of validity under §§101, 102 and 103, depends, albeit in potentially conflicting ways, on the content and completeness of the supporting specification and drawings. The patent scrivener should identify these issues of concern and prepare the patent specification to balance these offsetting issues in accordance with the commercial objectives of the client.

Computer-related inventions are often protected by claims that recite such inventions in terms of 'means-plus-function' language, as permitted by 35 U.S.C. § 112, ¶ 6. This paragraph statutorily permits incorporation of the written disclosure into the claims for the purpose of construing their scope. Thus, a means-plus-function claim appended to one specification may be interpreted differently than the same claim attached to a different specification. Alternatively, two claims, one reciting a particular element using a limiting term and a second claim drafted in the means-plus-function format so as to avoid the use of that term, may both be construed to be of the same scope and to read on that element.

Three recent decisions by the Court of Appeals for the Federal Circuit, Fonar Corporation v. General Electric Company, 107 F.3d 1543, 41 USPQ2d 1801 (Fed.Cir. 1997), Robotic Vision Systems, Inc. v. View Engineering, Inc., 112 F.3d 1163 (Fed.Cir. 1997), and Gentry Gallery, Inc. v. Berkline Corporation, 1998 U.S. App. Lexis 1079 (Fed. Cir. 1998), discuss the requirements of § 112, ¶ 1. Fonar and Robotic Vision, both discussed below, indicate that the inclusion of program flow charts or source code listings is no longer necessary to satisfy the 'enablement' and 'best mode' requirements of § 112, ¶ 1. Yet, as will be discussed herein, the requirements of §§ 101, 102, 103, as affected by § 112, ¶ 6, may still dictate that the patent scrivener prepare a specification that will exceed the minimum requirements now required under § 112, ¶ 1. Gentry Gallery, which involved a mechanical-type invention, as discussed below, shows how the 'written description' requirement of § 112, ¶ 1 may limit the scope of claims.

In Warner-Jenkinson Co. v. Hilton Davis Chemical Co., 41 USPQ2d 1865 (1997), the Supreme Court and the Federal Circuit, in a series of decisions citing Warner-Jenkinson, have confirmed the continued existence of the Doctrine of Equivalents albeit in a restricted form. These decisions confirm the use of the written description in determinations not only of literal infringement of claims, whether drafted in a means-plus-function format or not, but also of infringement under the Doctrine of Equivalents.


In preparing a patent application directed to computer software, the drafter of the patent application has a variety of ways in which to describe the invention. The computer software invention could be described, for example, at a very high level only in terms of its generalized functions and without any flow diagrams or software source code. The software invention could also be described in somewhat greater detail, in addition to disclosing the generalized functions of the software, by providing detailed flow chart diagrams that show the functions of the software by tracing the actual steps that a user would undertake in the process of the program, without actually providing an example of source code that a programmer would use in implementing the invention on a computer. At the level of greatest detail, the software invention could be described, not only by disclosing the general functions of the software and by providing flow chart diagrams, but also by providing a copy of the source code that a programmer would use in implementing the invention on a computer. Often, the level of disclosure chosen by a patent drafter has more to do with the level of sophistication of the inventors or the level of development of the technology at the time the application is drafted than with the intent of the drafter. Yet, the careful patent drafter should be aware of the shifting ground of court decisions and U.S. Patent and Trademark Office (USPTO) practice that determine the extent to which such inventions must be disclosed in order to satisfy the various statutory requirements.

In the U.S. patent law, 35 U.S.C. §112 sets forth the requirements for the disclosure of an invention. Paragraph 1 of §112 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 inventer of carrying out the invention.

Fonar and Robotic Vision demonstrate the current view of the Federal Circuit with regard to the issue of the sufficiency of disclosure of computer software patent applications in the context of the 'enablement' and 'best mode' requirements of § 112, ¶ 1, that is, the requirement that a patent application describe the invention in sufficient detail so as to enable one skilled in this technology to make and use the invention and so as to disclose the best mode known to the inventor for carrying out the invention. These recent decisions will undoubtedly impact upon the manner and breadth of disclosure that a patent drafter will feel compelled to include in a computer software patent application.

In Fonar, the Federal Circuit held that the § 112, ¶ 1 best mode requirement of disclosing the software used in a magnetic resonance imaging invention was satisfied merely by describing the functions of the software without actually including in the specification either software program source code or process flow charts. According to the court, writing software program code, whose function is disclosed in the specification, is normally within the capability of one skilled in the art to prepare without requiring undue experimentation.

The Fonar plaintiff was the exclusive licensee of two patents directed to a technique for using nuclear magnetic resonance, or magnetic resonance imaging. U.S. Patent No. 4,871,966 discloses a method and apparatus for using such a machine to obtain multiple image slices of a patient's body at different angles using a single scan. In defending against a charge of infringement, General Electric claimed that the '966 patent was invalid for violating the best mode requirement because the patent inadequately disclosed two software subroutines for accomplishing the claimed imaging.

The court agreed with the jury's finding that the best mode requirement was satisfied. There was evidence that the software and certain hardware were part of the best mode and that the '966 patent specification contained a sufficient description of the software subroutines. Judge Lourie, writing for the court, stated that,

[a]s a general rule, where software constitutes part of a best mode of carrying out an invention, description of such a best mode is satisfied by disclosure of the functions of the software. This is because, normally, writing code for such software is within the skill of the art, not requiring undue experimentation, once its functions have been disclosed. ... [W]hat is within the skill of the art need not be disclosed to satisfy the best mode requirement as long as that mode is described. Stating the function of the best mode software satisfies that description test. ... Thus, flow charts or source code listings are not a requirement for adequately disclosing the functions of software. 107 F.3d at 1549.

The court cited In re Hayes Microcomputer Prods., Inc. Patent Litigation, 982 F.2d 1527 (Fed.Cir. 1992), as support for its pronouncement that merely disclosing the function of the best mode software satisfies the best mode requirement even without disclosing flow charts or source code listings for the software.

In Robotic Vision, the Federal Circuit held that the best mode requirement in § 112, ¶ 1 was not violated by a patent that did not use the word 'software' because it was clear that using software was the only mode that existed for practicing the invention and that the use of software with this invention was plainly apparent to one skilled in the art.

The plaintiff is the assignee of U.S. Patent No. 5,463,227, which discloses a method of using a three-dimensional sensor in order to scan and inspect the leads of integrated circuit chips. The method requires a device that contains motors for moving the sensor along the x- and y-axes, but the specification does not disclose how the motors that move the sensor are controlled. A patent drawing of an embodiment of the invention lacks any means connected to the motors for controlling them. The district court granted View Engineering's motion for summary judgment of patent invalidity on the grounds that the patent failed to disclose the best mode because the software, the best known mode for practicing the invention, had not been disclosed. The district court distinguished the Federal Circuit's holding in Hayes, that disclosure in a patent of software code is not necessary if the functions of the software are disclosed therein, because the '227 patent contained no disclosure at all that would lead one skilled in the art to use software.

The Federal Circuit reversed the holding of the district court on the issue of best mode. Robotic argued that, because the use of a computer or software was not claimed in the patent, it was not obligated to disclose the software in order to satisfy its best mode obligation. The court rejected this argument, stating that Robotic was nevertheless not exempted from the requirements of a best mode disclosure, since carrying out the invention usually involves more than just what is expressly claimed. However, Judge Lourie, again speaking for the court, agreed with Robotic that the specification was adequate to lead one of ordinary skill in the art to use software in the invention, stating that:

it is plainly apparent that a computer, operating under software control, is to be interfaced to the device for controlling the movement of the sensor. Something must be connected to the device for providing control signals to the motors and for receiving information from the linear encoders concerning a position of the sensor, and there is no dispute that that something is a computer. 112 F.3d at 1166.

According to Judge Lourie, the record made clear that a software program was the only mode that was contemplated for or that was involved in carrying out the invention. Moreover, it would have been apparent to one skilled in the art, knowing that software was used in the prior art system, to use software to implement the improved scanning method claimed in the patent. Therefore, the patent complied with the best mode requirement because the use of software was plainly apparent to one skilled in the art and was implicit in the disclosure as the best mode of carrying out and implementing the invention.

Judge Lourie continued and held that there was no genuine issue as to whether one skilled in the art would have known how to create specific software code for the purpose of the invention. As previously held in Hayes and Fonar, when disclosure of software is required, it is sufficient to disclose the functions of the software, it being accepted that creation of the specific source code is within the skill of the art. In this case, the court said, the functions that a software program could instruct the computer to perform for controlling the machine were readily apparent from the '227 patent specification, which describes scan paths and parameters for full-tray scanning.

These two recent Federal Circuit cases both approve the invention disclosures in patent specifications directed to computer programs that include merely a set of functions that the computer is to perform in carrying out the invention but that don't actually provide any software source code or flow charts for use in creating such software source code. These two decisions represent a recognition by the courts that one of ordinary skill in the art of computers, i.e., a software programmer, would be able without undue experimentation to reduce such a disclosure of generalized functions to computer software that implements the disclosed invention, and that disclosures that divulge merely the generalized functions of the software invention do indeed satisfy the statutory best mode and enablement requirements.

Thus, the Fonar and Robotic Vision cases give guidance for the preparation of a patent application protecting a programmed computer invention, namely that the drafter need not disclose all. It is statutorily sufficient under § 112, ¶ 1 for a patent drafter to include in the specification the generalized functions of the invention, it being understood that the computer programmer implementing the invention would be able to prepare the software code needed to satisfy these disclosed functions. Neither process flow charts nor an actual example of software code, which could run on a computer without change, need be disclosed in the application.

These decisions represent a realization by the Federal Circuit of the real-world maturation of the abilities and the sophistication of computer programmers such that programmers are now, more than ever, able to create programs based upon even the skimpiest of disclosures. More importantly, these decisions reflect a recognition by the Federal Circuit that computer programmers with ordinary skill in the art can reduce such functional disclosures to software without 'undue experimentation'. As a result, the Federal Circuit has been willing to adopt a more flexible attitude toward the § 112, ¶ 1 disclosure requirements for computer-related inventions.

Yet, as will be discussed, due to this relaxed disclosure requirement, the patent drafter is now put in a quandary as to how much to disclose. Generally, drafters must balance the §112, ¶ 1 requirement to provide an enabling disclosure of the invention against the competing goal of expanding the scope of claim infringement, as well as against issues raised by §§ 101, 102 and 103. According to the Federal Circuit, less disclosure is still enabling of the invention. However, the question that needs to be asked is whether a patent disclosure of mere function will create problems for the patent holder when it seeks to secure approval of its patent application from the USPTO and to ensure that a competitor's product or process falls within the scope of its patent claims.


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