In a previous post, we reviewed a Milwaukee tool patent application for a reciprocating saw blade where the successful appeal was based on functional limitations of the claim. In that case, a critical point was that the structure in the cited art was significantly distinct from the detailed structure disclosed in Milwaukee's application. In another recent PTAB decision, the appellant, Fuji, found itself on the losing side of that same issue - primarily because the structure in the cited art closely matched the structure in Fuji's application.

Specifically, Fuji's application (US 14/344,789) relates to an electromagnetic contactor including fixed contacts interposed in a current path and a movable contact and arranged to generate Lorentz forces opposing electromagnetic repulsion forces causing the movable contact to separate from the fixed contacts when current is conducted. Claim 1 on appeal recites:

1. An electromagnetic contactor comprising:
a contact mechanism including a pair of fixed contacts having fixed contact portions interposed in a current conduction path, and a movable contact having a pair of movable contact portions contacting to and separating from the pair of fixed contact portions, wherein at least one of the pair of fixed contacts or the movable contact is formed in a shape to form magnetic fields generating Lorentz forces opposing electromagnetic repulsion forces generated in an opening direction between the fixed contact portions and the movable contact portions when current is conducted, and external connection conductors, each having a fixed portion connected to external connection terminals of the fixed contacts and extending laterally outwardly from a case, an attachment direction of each of the fixed portions fixed to the external connection terminal of the fixed contacts being set to cross a current flow direction flowing through the movable contact.

One of Fuji's primary arguments was that the applied references do not disclose or suggest that at least one of a pair of fixed contacts or a movable contact is shaped to form magnetic fields that generate Lorentz forces opposing electromagnetic repulsion forces in an opening direction between the contacts when current is conducted, as recited in claim 1. Specifically, Fuji alleged that the cited reference (Takaya) does not disclose a structure for its fixed contact or its movable contact (e.g., an L-shaped structure, as described in paragraph 26 of Appellants’ Specification and depicted in Appellants’ Figure 3(a)) that would generate the Lorentz forces recited in claim 1.

However, in the Answer, the Examiner switched the rejection to rely on another reference (Koyoshi) rather than Takaya. This is a common tactic where some Examiners fail to actually consider arguments until on appeal, and then when realizing that the features is missing from one reference, switch to another reference that has the missing feature. That is why it is so important before proceeding to appeal to actually review all cited references in the rejection to see if the Examiner can re-form an obviousness rejection to better reject the claims. While it is unfair for the Examiner to be able to change the reasoning of the rejection, the rules at the PTO provide great flexibility to the Examiner. Here, unfortunately, Fuji was now stuck dealing with this new rejection. And furthermore, Kiyoshi showed a structure very similar to that structure in Fuji's application for the contacts. Once this was established, it was easy for the PTAB to affirm the Examiner since the burden switches to the appellant.  From the decision:

As Fuji had no evidence to meet its burden, this line of argumentation was unpersuasive.

While Fuji had several other arguments regarding claim construction, the desired narrow construction was not commensurate in scope with the claim wording and so was unpersuasive. In subsequent prosecution Fuji amended the claims to explicitly recite the more specific features and was able to better distinguish the cited art and more the case forward in prosecution.