Board Should Consider Appellee’s Grounds For Affirming Rejection Presented To Examiner During Reexamination, Even If Grounds Had Not Been Raised On Appeal
Bill Schertler | February 6, 2013
Rexnord Industries v. Kappos
January 23, 2013
Panel: Newman, Lourie, Prost. Opinion by Newman.
In 2003 Habasit filed an infringement suit against Rexnord in the United States District Court for the District of Delaware for infringement of its U.S. Patent No. 6,523,680 (the ’680 patent). Rexnord then requested inter partes reexamination of the ’680 patent, and the district court stayed the infringement suit pending completion of reexamination.
On reexamination, the examiner held all of the claims in the ’680 patent unpatentable for anticipation and obviousness. Habasit appealed the examiner’s decision to the United States Patent and Trademark Office (PTO) Board of Patent Appeals and Interferences (Board). On appeal, the Board reversed the examiner’s decision and held the claims patentable.
Rexnord appealed to the CAFC. The CAFC affirmed that the claims are not anticipated, and reversed the Board’s determination that the claimed invention is not obvious in view of certain prior art.
The ’680 patent is related to a mechanical conveyor belt that is formed of rows of belt modules interlinked by transverse rods to form an endless belt that is capable of following a curved path. The spaces between the belt modules are blocked by plastic “webs” so that the spaces are too small to pinch small items such as a finger; the claims state that the spaces are smaller than 10 mm in diameter. Claim 1 is representative (boldface added to the limitation here at issue):
1. A radius conveyor belt, comprising:
a plurality of belt modules …;
a pivot rod….;
wherein the web on the cross-rib extends in the direction of belt travel such that, when the belt is at maximum extension in the direction of belt travel, a space bounded by the web, an outer end of the first link ends and the sidewalls of second link ends has a diameter less than 10 mm.
Fig. 7 of the ’680 patent reproduced below shows the belt formed by the interlinked modules, with the critical “space” limitation marked as “Example Space,” also marked as space 200:
The Habasit patent describes that the space between the link ends has a diameter of less than 10 mm when the belt is at its maximum extension, “to prevent fingers from penetrating the grid.”
Before the Examiner on Reexamination
During reexamination, the examiner held all of the claims in the ’680 patent unpatentable as being anticipated and obvious.
Rexnord cited four references for the reexamination: U.S. Patent No. 6,382,405 (Palmaer), U.S. Patent No. 6,471,048 (Thompson), U.S. Patent 5,372,248 (Horton), and U.S. Patent No. 5,253,749 (Ensch). Each reference describes a conveyor belt comprising modules that are assembled similarly to the modules in the ’680 patent.
Two of the reference patents, Palmaer and Thompson, discuss the problem of objects such as fingers getting caught in the space between the modules, and state that the structure of their belt reduces the size of the space. Neither Palmaer nor Thompson states the size, or maximum size, of the space when the conveyor belt is at its maximum extension.
In its request for reexamination, Rexnord argued, inter alia, that “the only difference between the teaching of the Thompson ’048 Patent and the ’680 Patent is that the ’680 Patent teaches a design choice which allows pinching a small child’s finger having a diameter of less than 10 mm in the gap between adjacent links.”
However, in concluding that the claims were obvious, the examiner did not rely on the design choice argument. Instead, the examiner found that Horton shows all of the elements of independent claims 1 and 8 of the ’680 patent except for “a web adjacent the corrugated portion positioned such that a space . . . has a diameter less than 10 mm.” The examiner cited Thompson for teaching a web between modules to prevent pinching of objects between modules, and cited Palmaer and Thompson for showing a space sufficiently small to prevent pinching of small objects such as a finger.
The examiner concluded that it would have been obvious for a person of ordinary skill in this field to combine the Horton modules with the Thompson web to create a space with a diameter less than 10 mm to prevent pinching of small objects. The Examiner’s conclusion of obviousness relied on an interpretation of ‘space’ as allowing for situations where the space itself is completely closed or is part of a contiguous surface or body so as to have a diameter of 0 mm.
On Appeal to the Board
Habasit appealed to the PTO Board, and the Board reversed the Examiner ruling in favor of Habasit.
Habasit’s argument to the Board focused on the issue that the 10 mm maximum dimension of the space is not stated in any reference, and that some reference belts have no space. The Board, in agreeing with Habasit’s argument, found that “the dispositive issue on appeal is: did the examiner err in determining that both Palmaer and Thompson, Jr. disclose a space having a diameter of less than 10 mm as recited by the claims?”
The Board observed that the references do not state the dimensions of the space between modules, and “the Examiner has not identified where the prior art discloses that this space has a diameter of less than 10 mm as required by the claims.”
Regarding the Examiner’s interpretation of the term “space”, the Board stated that “[t]o the extent the Examiner’s rejection relies on an interpretation of ‘space’ as allowing for situations where the space itself is completely closed or is part of a contiguous surface or body…. so as to have a diameter of 0 mm, this interpretation essentially reads the limitation space, a positively recited feature, out of the claims.”
Rexnord’s request for rehearing
Rexnord requested rehearing, arguing that the 10 mm spacing limitation was inherent in the structures described in the prior art and that it was merely a design choice.
The Board denied the request for rehearing, responding that Rexnord had waived its inherency arguments for anticipation. The Board stated that “Rexnord’s reliance on ‘design choices’…. is more consistent with an obviousness analysis,” but did not discuss Rexnord’s arguments for obviousness.
The Board stated “Rexnord’s reasons as to why it would have been obvious to construct a space as recited in the claims were not the rationale of the Examiner’s rejection.”
Rexnord appealed the Board’s decision to the CAFC, criticizing the Board’s refusal to review all of the arguments that Rexnord had presented as grounds for unpatentability.
Before the CAFC
On appeal, the CAFC rejected Rexnord’s inherency argument, but agreed with its obviousness (design choice) argument.
Regarding inherency, the CAFC explained “anticipation by inherent disclosure is appropriate only when the reference discloses prior art that must necessarily include the unstated limitation, [or the reference] cannot inherently anticipate the claims.” The CAFC found that the precise less-than-10 mm size limitation is not inherent in Palmaer or Thompson.
Regarding design choice, the CAFC explained, all of the structural elements of the claims are shown in the references. A space that is small enough to avoid pinching of fingers is taught in the prior art, with the 10 mm dimension being a design choice that takes account of the size of fingers and other small objects.
Another aspect of the appeal was the Federal Circuit’s conclusion that the Board erred in reversing the examiner’s ruling of obviousness without considering any of the other grounds of obviousness that had been raised for reexamination. The CAFC rejected the PTO’s argument that Rexnord couldn’t argue grounds for affirming the rejection that were not articulated by the Examiner.
On appeal to the CAFC, the PTO took the position that the Board does not consider aspects beyond those relied on by the examiner. The PTO states that Rexnord’s argument that it would have been “a mere design choice,” in view of Horton and Thompson, to create a 10 mm space was not raised until Rexnord’s motion for Board rehearing. The PTO brief states that “[t]he Board correctly declined Rexnord’s invitation to reject representative claim 1 as obvious over the combined teachings of Horton and Thompson under this new theory – presented by Rexnord for the first time in its request for rehearing.”
However, the “new theory” was not new. The design choice argument had previously been presented to the examiner in the Request for Inter Partes Reexamination. The issue was fully raised before the examiner.
Citing numerous precedent, the CAFC stated that, on judicial review, the correctness of the decision appealed from can be defended by the appellee on any ground that is supported by the record, whether or not the appellant raised the argument.