The Federal Circuit decision in In re Durance is a rare precedential decision in an ex parteappeal from a Patent Trial and Appeal Board (PTAB) decision rejecting a pending patent application. The Court took the USPTO to task for making the rejection a moving target throughout the appeal process and failing to consider Reply Brief arguments addressing a new rationale in the Examiner’s Answer. This decision highlights how one-sided the ex parteappeals process can be, especially since the applicant here still has to pursue the merits of its case before the USPTO on remand.
The Patent Application At Issue
The patent application at issue was U.S. Patent Application 12/682,989 (assigned to Enwave Corp.), directed to methods and apparatuses for “microwave vacuum-drying of organic materials, such as food products and medicinal plants.” The court discussed apparatus claim 1, which includes the following means-plus-function “tumble” limitation at issue on appeal:
means for rotating the container inside the vacuum chamber so as to tumble the organic material in the container
Method claim 16 includes a similar limitation:
rotating the container inside the vacuum chamber so as to tumble the organic material in the container
The Cited Prior Art
The obviousness rejection on appeal was based on two prior art references:
- U.S. Patent No. 6,442,866 (“Wefers”). As described by the court, “Wefers teaches drying food products, like fruit and berries, by loading ‘transport receptacles’ containing the food products into a ‘treatment chamber’ operating at reduced atmospheric pressure, in which the food products are exposed to a heating source, including a microwave source.
- U.S. Patent Application Pub. No. 2005/0019209 (“Burger”). According to the court, Burger discloses “sterilizing containers in which a plasma treatment is executed” using “excitation of an electromagnetic oscillation so that the plasma is excited in a vacuum in the vicinity of the container regions to be sterilized.” Relevant to the rejection, “Burger teaches that the containers to be sterilized are inputted into a chamber ‘with a transport apparatus inside it, which produces an essentially rotating motion of the container during the transport from the arrival to the discharge in the chamber.'”
The Moving Target On Ex Parte Appeal
The Federal Circuit decision highlights the following rationales for rejection taken by the USPTO during the ex parte appeal:
- In the Final Rejection, the examiner referred to Figures 1, 6, and 7 of Burger and asserted that the “tumbling” limitation was met by the combination of Wefers and Burger because “the organic material inside the containers ‘will tumble when the container is in rotation’ [as taught in Burger] as ‘merely an inherent function of all rotating containers.'”
- In an Advisory Action, the examiner cited Burger’s Figure 8 of Burger, which the court described as “show[ing] containers rolling down an inclined plane through the vacuum chamber and rotating around their longitudinal axes.”
- In the Examiner’s Answer, the examiner asserted that “there is no structural difference between the claimed invention and the combined teachings of the prior art references.” (The examiner did not designate the “structural identity” finding as a new ground of rejection.)
- Before the Federal Circuit, the USPTO cited Figure 10 of Burger “as the true embodiment that matches Durance’s disclosed structure.”
In the Reply Brief, Durance pointed out a number of factual errors in the “structural identity” finding, and explained how the structure disclosed in the application differed from that of Burger, including the use of gears to cause the rotation at issue and the presence of dividers within the container to promote tumbling.
The PTAB upheld the examiner’s rejection stating,”given the appropriate selection of rotation speed and material for the inner surface of the container, tumbling would be inherent” (emphasis added). The PTAB disregarded Durance’s Reply Brief arguments, citing 37 C.F.R. § 41.41(b)(2) and finding they were “not responsive to an argument raised in the [Examiner’s] Answer.” The PTAB denied Durance’s Request for Rehearing, asserting that neither the examiner’s rejection nor its decision were based on the “doctrine of inherency,” and again refusing to consider Durance’s Reply Brief arguments because Durance allegedly had not pointed out “where a new argument requiring such response was raised in the [Examiner’s] Answer.”
The Federal Circuit Decision
The Federal Circuit decision was authored by Judge Reyna and joined by Judges Lourie and Chen.
The court first took the USPTO to task for making the rejection on appeal a moving target, both with regard to which teachings of Burger were being relied upon and whether the rationale was based on inherency or structural identity:
Throughout this examination, the Patent Office continually shifted its position on which Burger structures and what characteristics of those structures are the bases for the Office’s grounds of rejection.
The court found the PTAB’s reliance on 37 C.F.R. § 41.41(b) misplaced. That rule provides in relevant part (with emphasis added):
Any argument raised in the reply brief which was not raised in the appeal brief, or is not responsive to an argument raised in the examiner’s answer, including any designated new ground of rejection, will not be considered by the Board for purposes of the present appeal, unless good cause is shown.
The court agreed that the structural identity rationale was first raised in the Examiner’s Answer such that it “was therefore proper under § 41.41(b)(2) for Durance to respond to the structural identity argument” in the Reply Brief.
The court rejected the USPTO’s argument that Durance should have petitioned to have the examiner’s answer designated as a new ground of rejection:
[Section] 41.41 states that a showing of good cause is only required if the argument is not responsive to an argument raised by the examiner. Here, Durance’s reply brief was responsive to the examiner’s answer and included citations indicating the new arguments to which Durance was responding. …. It was error for the Board to find such argument waived.
The court therefore vacated the PTAB decision and ordered the PTAB to consider Durance’s Reply Brief arguments on remand.
The One-Sided Appeal Process
This case highlights how frustrating and one-sided the ex parte appeal process can be. Even as the Examiner shifted the rationale for rejection, the PTAB refused to consider the applicant’s arguments. And, even though the Federal Circuit decision was favorable to the applicant, Durance still has to prevail on the merits on remand. This case also reinforces my practice of requesting an oral hearing in most ex parte appeals. While it’s possible the PTAB still would have ignored Durance’s arguments, I’d like to believe it would have been harder for the judges to be so dismissive in person.
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