Our last post discussed transitional phrases in patent claims and how the choice between comprising, consisting essentially of, and consisting of affects claim scope. That post focused on how these phrases are interpreted during claim construction in light of support in the specification, and the somewhat unusual situation where the PTAB actually strayed from the conventional interpretation. This post continues that theme by looking at how the closed nature of “consisting of” plays out in the context of obviousness rejections.
Claims using “consisting of” are closed to unrecited elements and so there are situations where a claimed invention can be distinguished from a combination of prior art resulting in additional elements being present. For example, applicants commonly argue that a prior art reference—or a combination of references—fails to meet a “consisting of” claim because the references include extra components. This argument can be effective when the examiner modifies an embodiment in one reference by adding a feature from a second reference, and the resulting structure or system would include additional elements not found in the claim.
But, a common misstep that can sometimes occur includes relying on the exclusionary scope of “consisting of” to argue against combinations of prior art under §103 formed by selecting individual elements to combine from the references. For example, arguing merely that the transitional phrase excludes extra elements may be less effective in situations where the examiner constructs the rejection by selecting individual elements from various references and relying only on those specific components in combination—not the additional features or elements of the particular embodiments in each reference. Here, the presence of extra material in the references is a red herring.
An example case where the examiner builds a combination, element-by-element, from multiple references to match the claimed structure can be found in a recent PTAB case: Appeal 2024-003590
Application 16/492,117. The examiner combined individual elements from various references to reach the claimed combination.
The application relates to an orthopedic standing and walking aid for therapy, as an example. Claim 1 on appeal is reproduced below:
1. An orthopedic standing and walking aid, consisting of:
- a carriage which is displaceably mounted on a running rail in a longitudinal direction of the running rail,
- an approximately C-shaped frame suspended on the carriage by a suspension device including a spring so that the C-shaped frame is elastically supported in a vertical direction, wherein the running rail is mounted on a further rail arrangement so as to be displaceable transverse to the longitudinal direction of the running rail,
- a saddle which is arranged on the C-shaped frame approximately in rectilinear alignment below the suspension device, with
- a saddle post extending from the saddle into a sleeve connected to the C-shaped frame, wherein the saddle
post is slidably mounted in the sleeve,
- a height-adjusting spring arranged below the saddle post, which exerts an upward preload on the saddle and allows for adjusting a height of the saddle, and
- a lock with which the height-adjusting spring is lockable, wherein the saddle has an elongate slim shape whereby a person sitting on the saddle arranges his/her legs directed downwards on opposite lateral sides of the saddle, wherein the C-shaped frame does not include a backrest or an abdominal support, and the C-shaped frame is shaped so that a person’s body does not touch the C-shaped frame when the person is sitting on the saddle.
The Appellant argued that the use of the “consisting of” transitional phrase in the claim meant that the examiner’s rejection was improper because various cited references had elements not included in the claims, in that each of the cited references required additional features. The Appellant identified elements in certain references that were additional to the teachings cited by the Examiner, but did not argue that one of ordinary skill would understand any of the additional elements were required by the cited references. The PTAB explained the problems with this argument as follows:
… the Examiner has identified particular teachings in each of the references, explained their pertinence, and provided rationales to show one of ordinary skill would use each of these teachings in combination as claimed… Appellant does not persuade us that [the Examiner’s] findings are disturbed by the references’ additional elements. Appellant has not provided sufficient evidence or technical reasoning to persuade us that the claim is non-obvious in view of the cited art. Thus, we are not persuaded of error in the Examiner’s rejection of claim 1 as obvious in view of the combined teachings of [5 references].
So, when a rejection relies on modifying an existing embodiment that ends up with more than the claimed elements, the “consisting of” language may provide a useful argument. But if the examiner is instead (expressly) selecting only the claimed elements from different references, then a more productive approach may be to scrutinize how the examiner is selecting and building the combination, and what reasoning/evidence is relied on in support thereof. For example, consider whether the examiner has provided a clear and supported reason for selecting each element from the references from among the various elements shown in the reference, and/or whether the examiner articulated a reasoned rationale for combining the selected elements in the manner claimed.