VI.Applying for a Software Patent

Software-based inventions can be claimed in a straightforward manner using method claims, where the elements of the claims are the steps of the method performed by the new software technique. If a separate patent application is filed for each innovative technique used in a computer program, the drafting of the patent application can be quite straightforward. But while it is possible for a competent computer programmer to draft a patent application, and a programmer should definitely take an active role in the preparation of the application, often an experienced patent attorney or patent agent can draft claims that may have broader or better coverage.

Although it is not required by law, once you have identified an innovative technique you should conduct a search of the prior art. This search starts with a literature review (journal and magazine articles, books, conference proceedings, and research reports) to find the material closest to the technique. The online collection of patents and pending applications offered by the patent office should also be searched. This can be done either by looking for keywords in the text, or by the classification numbers assigned to each patent. The results of the search will let you know how broadly you can claim the invention, and give you an idea of the language used to describe similar inventions.

The first step after identifying the innovative technique and determining its potential scope is to prepare a simple diagram or flowchart showing its major steps and what causes a transition from one step to the next. Additional diagrams can be prepared to show more details for particular steps. Then write the specification describing what is done at each step and how to do it. Always describe both the best way to perform the step (the “best mode,” or “preferred embodiment,” as required by Section 112) {FN77: 35 U.S.C. §112} and all the possible alternative implementations that you can think of. Describing a variety of implementations lessens the possibility that a particular step in the claims will be read as covering only the preferred embodiment.

But it is equally important that you don’t describe something that you don’t claim. It may not be possible to assert the doctrine of equivalents to cover the disclosed but unclaimed embodiments. {FN78: Johnson & Johnston v. R.E. Service, 285 F.3d 1046, 62 USPQ2d 1225 (Fed. Cir. 2002)} In light of the Supreme Court’s decision in Festo, {FN79: Festo v. Shoketsu Kinzoku Kogyo Kabushiki Co., __ U.S. __, 62 USPQ2d 1705 (2002)} the doctrine of equivalents likely does not capture subject matter that the patent drafter reasonably could have foreseen during the application process and included in the claims. This can be solved by having a generic claim that encompasses all of the described embodiments, as well as specific claims for important embodiments.

The first, and broadest, claim is then written as a method claim based on the steps shown in the diagram, with each step of the method briefly describing the corresponding step in the diagram. As part of the method claim, any particular hardware components that are necessary for performing the steps of the method can be conveniently introduced as part of the preamble, so the form of the claim is:

A method operating on a digital computer, said digital computer comprising [the parts of the computer cited in the method steps], the method comprising:

[Step one of the method];

[Step two of the method];

. . .; and

[The last step of the method].

It is not necessary to include each step of the method in the claims. It is only necessary to include the steps critical in distinguishing the method from the prior art in the field. Claims are not algorithm descriptions but indicate what must be present for the patent to be infringed and how the invention differs from the prior art.

As written in the form above, the steps of the method can occur in any order for the claim to be infringed. One can think of it as having a checklist listing the steps in the claim, and whenever one is performed, it is checked off. Steps can be checked off as many times as they occur. When each step has been checked off, the claimed method has been infringed.

But sometimes a court might misinterpret the claim as requiring the steps to be performed in the order specified, particularly if the steps are performed in that order in every embodiment of the invention described in the specification. If there is a particular order in which the elements of the claim should occur, that should be specified by using a connective such as “and then” between those elements. Otherwise, a transitional phrase like “the method comprising the following steps, in any order” may be used to make it clear that order is not a consideration.

In addition to claiming the software-based invention as a method, you can (and should) also claim it as an apparatus (essentially, the computer that executes the method) and as an article of manufacture (the floppy disks that are used to distribute the invention to users). Though these claims may look very similar to the method claim, they are infringed by different acts and may reach different infringers. For example, a method claim would be infringed when the method is executed, but an apparatus claim would be infringed when a program implementing the method is loaded into the digital computer. An article-of-manufacture claim is infringed when the floppy disk used to distribute a program implementing the method is created or sold.

Each method claim can be used as the basis for both apparatus and article-of-manufacture claims if some boilerplate language has been included in the specification. To enable an apparatus claim, the following language might be used:

Fig. X illustrates a representative digital computer system that can be programmed to perform the method of this invention. [Describe each component in the figure, giving emphasis to any component that plays a particular role in the method.]

Other digital computer system configurations can also be employed to perform the method of this invention, and to the extent that a particular system configuration is capable of performing the method of this invention, it is equivalent to the representative digital computer system of Fig. X, and within the scope and spirit of this invention.

Once they are programmed to perform particular functions pursuant to instructions from program software that implements the method of this invention, such digital computer systems in effect become special-purpose computers particular to the method of this invention. The techniques necessary for this are well-known to those skilled in the art of computer systems.

Then the following can be used for the apparatus claim based on method claim N:

A digital computer system programmed to perform the method of claim N.

This form of dependent claim is somewhat different from the normal one that adds a new element or limitation to its parent claim, but remains in the same statutory class (method, machine, article of manufacture). This is a claim for a machine (“a digital computer system”) dependent on a method claim. But the Manual of Patent Examining Procedures specifically permits such dependent claims:

The fact that the independent and dependent claims are in different statutory classes does not, in itself, render the latter improper. Thus, if claim 1 recites a specific product, a claim for the method of making the product of claim 1 in a particular manner would be a proper dependent claim since it could not be infringed without infringing claim 1. Similarly, if claim 1 recites a method of making a product, a claim for a product made by the method of claim 1 could be a proper dependent claim. On the other hand, if claim 1 recites a method of making a specified product, a claim to the product set forth in claim 1 would not be a proper dependent claim if the product might be made in other ways. {FN80: §608.01(n), Manual of Patent Examining Procedures, United States Patent and Trademark Office, page 600-77 (8th Ed., August 2001)}

In In re Kuehl, {FN81: 475 F.2d 658, 177 USPQ 250 (CCPA 1973)} the Court of Customs and Patent Appeals considered a dependent claim for a process using a specific composition (a new zeolite) of matter previously claimed:

11. A hydrocarbon conversion process which comprises contacting a hydrocarbon charge under catalytic cracking conditions with the composition of claim 6.

The court found that the dependent claim was proper, stating:

We believe the constitutional purpose of the patent system is promoted by encouraging applicants to claim, and therefore to describe in the manner required by 35 U.S.C. 112, all aspects of what they regard as their inventions, regardless of the number of statutory classes involved. The dependent claims on appeal to the use of the new zeolite in the same application with the composition claims do not materially increase the scope of protection of his inchoate patent property under 35 U.S.C. 154, which already includes the right to exclude others from making, using, or selling the composition by allowance of claims thereon, but they do tend to increase the wealth of technical knowledge disclosed in the patent by encouraging description of the use aspects of his invention in the manner required by 35 U.S.C. 112, paragraph 1. {FN82: 475 F.2d at 666-667, 177 USPQ at 256}

Of course, if during the prosecution of the patent application the examiner objected to the form of the dependent claim and for reasons of time it was undesirable to contest the objection, it would be simple to rewrite the dependent claim in independent form. All that would be necessary would be to simply copy-and-paste the method claim into the dependent claim, indicate in the prosecution history that the new claim is identical in scope to the original claim and that there should be no prosecution history estoppel based on the amendment, and pay the additional fee for the new independent claim.

A similar thing can be done for an article-of-manufacture claim. The boilerplate language would be something like:

Computer programs implementing the method of this invention will commonly be distributed to users on a distribution medium such as floppy disk or CD-ROM. From there, they will often be copied to a hard disk or a similar intermediate storage medium. When the programs are to be run, they will be loaded either from their distribution medium or their intermediate storage medium into the execution memory of the computer, configuring the computer to act in accordance with the method of this invention. All these operations are well-known to those skilled in the art of computer systems.

The term “computer-readable medium” encompasses distribution media, intermediate storage media, execution memory of a computer, and any other medium or device capable of storing for later reading by a computer a computer program implementing the method of this invention.

Then the following can be used for the article-of-manufacturing claim based on method claim N:

A computer-readable medium storing a computer program implementing the method of claim N.

This way of claiming software-based inventions simplifies the examination of the application, because it concentrates on the new method that is the heart of the invention while providing coverage for the invention not only as a method but also as an apparatus that runs the method and articles of manufacture used to distribute programs implementing the method. It means that your claims will generally be in groups of three: the method claim (either an independent claim or a claim dependent on a previous method claim), a dependent apparatus claim, and a dependent article-of-manufacture claim, the latter two based on the method claim.