The drafting of process or method claims has been significantly altered by In re Bilski.14 Previously, the conventional best practice in claim drafting for method claims was to focus specifically on the method steps being performed, omitting reference to environment, and minimizing mention of the actor and workpiece as much as possible. In view of Bilski, the best practice in process claim drafting may substantially change. Bilski has, in effect, required that any process claim pass the “machine-or-transformation” test. This test requires either that the claimed process be tied to a particular machine or that the claimed process transform an underlying physical object. The putative rationale for the test is that it avoids the claiming of an abstract idea or, more particularly, avoids claims that exhaust a fundamental concept by covering every instance thereof.  

In some areas of patent practice, claiming the invention will not change at all. Two such areas are methods of synthesizing chemicals and methods of manufacture. If a method is synthesizing a chemical from a precursor of some sort, it will meet the “transformation” prong of the machine-or-transformation test. Likewise, methods of manufacture that involve assembly of parts of a physical product will similarly meet the transformation prong. In general, the transformation prong of the test will be met in any method claim that relates to the alteration of some physical object. The greater the degree of alteration, the more clearly the method claim will pass the test. For example, the Federal Circuit indicated that a method of curing rubber would be expected to pass the transformation test. In such a method, the rubber is being physically altered and, consequently, the method would be deemed to be proper subject matter for a patent.  

The Federal Circuit seems to want the claim to be tied to a particular machine in order to avoid claims that are excessively broad.

In view of the fact that claims to methods of synthesis and manufacture are likely proper subject matter, patent practitioners will undoubtedly attempt to characterize other kinds of method claims in such a way. However, there may be limits on how this use of the transformation test can be applied. It is possible that the use of a very generic term for the product to be manufactured may dissatisfy a future Federal Circuit panel. For example, a “method for manufacturing widgets” would seem more tenuous than a “method for manufacturing means for illumination,” which would, in turn, seem more tenuous than a “method for manufacturing light bulbs.” In other words, the more specific and concrete the product is, the higher the likelihood that the Federal Circuit will deem the transformation to pass the test.

Additionally, practitioners seeking to protect software innovations may seek to characterize their invention in terms of a method of producing a transformation in a signal, a magnetic medium or a similar recording structure. The Federal Circuit specifically avoided discussing whether such a transformation would qualify, which casts a shadow of doubt over whether the Federal Circuit would consider such a transformation adequate. In view of the Federal Circuit’s decision in In re Nuijten, 15 it seems unlikely that the transformation of a transient signal would be considered an adequate transformation. Producing a transformation in magnetic media or similar structures may be more successful.

Moving on from “transformation,” we encounter the “machine” portion of the test. In general, claim drafters could meet this test by including a particular machine somewhere in the claim. There are several options for how the particular machine can be included, which may lead to different results as to whether subject matter is proper.

The first option is to mention the machine as environment. For example, the particular machine may be identified in some nonlimiting way within the body of the claim. One possibility is if the particular machine were mentioned within an optional recitation found in the claim, or found in only one of several embodiments covered by a claim. Another way that the particular machine can be mentioned as environment is to mention the particular machine. Thus, for example, a claim may recite “a method for counting on an abacus,” without further reference to the abacus within the body of the claim. Thus, arguably, the feature “counting on an abacus” is merely an intended use and not a limitation on the claimed method.

However, this first option is the least likely to be successful. The Federal Circuit seems to want the claim to be tied to a particular machine in order to avoid claims that are excessively broad. If the machine does not serve as a meaningful limit on the method, it is unclear how the recitation of the particular machine would serve to prevent the claim from appropriating an entire fundamental idea. Thus, it would not seem to be the best practice to rely solely on an optional or environmental recitation of a particular machine.

A second approach is to recite a particular machine as a workpiece. In a method of ferrying cars, for example, cars are workpieces: they are things being acted upon. The operations described are not performed by the cars, but on the cars. In some cases, having a particular machine as a workpiece may result in a transformation. In other cases, however, a process like ferrying boats may not be deemed to significantly transform the workpiece in question.

This second option is more likely to be successful than the environmental claiming. Indeed, since a method that did not include the workpiece could not infringe the claim, it is reasonably arguable that the method is tied to the workpiece. There are two factors, however, that make this claiming approach risky. First, the workpiece may not be considered to be a limitation on the method step itself. For example, in the method of ferrying cars, the method steps may not really depend on the fact that the load being carried is a car, as opposed to a large brick. It could be argued by an adverse party that the workpiece is not a real limitation of the claimed process and thus the subject matter is not proper.

If a machine is specified for only one step of a particular claim, care should be taken to ensure that the selected step is at the heart of the invention and not merely tangential to the invention.

The second factor that makes this approach risky is US Patent and Trademark Office (PTO) interpretation of the machine prong of the test. In reviewing a number of claim rejections issued by the PTO after Bilski, most of the rejections seem to focus on whether there is a stated actor for the claimed method, while ignoring the issue of whether a workpiece is present. In some art units, concern over overly broad claims may also encourage examiners to request that applicants specifically identify the particular machine performing a claimed method. Thus, there may be some institutional bias against considering the workpiece to be a sufficient tying to qualify the claimed subject matter as proper under the machine prong of the Bilski test, leading to rejections of the claims.

The clearest way to tie a particular machine to a claimed method is to state that the machine performs one or more steps of the method. Thus, in the example of a method of ferrying, the ferry itself would be the particular machine that performs the method. One problem with this approach, however, is that the more effectively it ties the process to a specific device, the more limiting the proposal becomes.

Again, as in the case of the transformation, the machine may be specified more or less particularly. The specification of the machine as a “widget” or some other highly generic term is unlikely to pass the test, because it is unlikely that a “widget” (as such) would qualify as a particular machine. At the other end of the spectrum, a device specified by manufacturer part number would qualify as a particular machine, but the resultant claim would (one expects) be trivial to design around.

Toward the center of the spectrum is the recitation of a “processor” or “controller” as the specific device. For many inventors of electronic business method claims and many other software-related claims, this approach may be attractive. Again, there is a balance of risks associated with this approach. While “processor” and “controller” are more specific than “widget,” they are still rather generic. Furthermore, the Federal Circuit specifically excluded the discussion of computer-implemented inventions from its discussion, leaving doubt about the level of specificity required.

When tying the steps of a method to a particular machine, one approach that appears to be acceptable is to recite, “wherein the method is performed by [the particular machine].” Another option is to specify that one particular step is performed by a particular machine. If a machine is specified for only one step of a particular claim, care should be taken to ensure that the selected step is at the heart of the invention and not merely tangential to the invention.

Tying to certain categories of process steps may not be helpful. The Federal Circuit has indicated that gathering inputs by machine is generally an insufficient tying. The analysis the Federal Circuit used for the relevance of the tying in the machine prong of the test was a “solution” test.

The Federal Circuit indicated that the analysis of the claim would proceed in this case with respect to a problem-solution analysis. Accordingly, those parts of the method claim intimately connected with the problem to be solved are the parts where machine-tying is relevant. In the case of data-gathering, this is viewed as “pre-solution activity.” Merely storing the results of processing, even where the storing was done by a particular machine, would likely be considered “post-solution activity.” On the other hand, display of processing results, if necessary to solve the problem in the conventional art, could be considered activity that is part of the solution.  

Accordingly, if claims are drafted with fewer than all the steps being performed by a specified machine, care should be taken that the steps tied to a particular machine are those that are directly involved in the solution of the problem for which the invention is intended. Simply tacking on a step to the method, where the new step is tied to a machine, is likely to be unacceptable to the Federal Circuit as it would appear to be “extra-solution activity,” not at the heart of the claimed invention.  

It should be noted that the new drafting approach is not necessarily limited to the claims, as such. Patent practitioners may wish to draft their applications, particularly those for business methods, so as to maximize tying of the claimed processes to particular machines. If such machine is a “processor” or “controller,” the specification should be careful to provide some general description and examples of embodiments of the processor or controller, so the terms are given a broad yet sufficiently particular meaning. Furthermore, practitioners should consider providing a problem-solution discussion in the application, in which various parts of a claimed method are important to the solution of various problems, so as to provide multiple options for tying the method to particular machines.

Bilski should provide fodder for litigation of US patent claims to processes for many years to come, assuming it is not overturned by the US Supreme Court. The cautious patent prosecutor should take care to plan for the risks of claims being deemed to be addressed to improper subject matter. Such plans can include tying the methods to processes or drafting the methods to include the transformation of a real physical object.