When does the Patent Practitioner carry the burden of proof?

Written by Mark Terry

In the last decision of this past Thursday, the Board of Patent Appeals and Interferences (BPAI) reiterated the rule that attorney argument is not enough to meet certain burdens in course of patent prosecution. As a Board Certified patent lawyer in Miami with a sizable docket of cases, I’m constantly staying abreast of the current state of the law on issues relating to patent prosecution.

The Patent Examiner in the Ex parte Zechlin case asserted that a characteristic of the claimed chemical process was found in a prior art patent. Specifically, the Patent Examiner found the claimed cyclic ketone removal characteristic was “inherent” in the chemical process shown in the Forlin (U.S. Pat. App. No. 2004/0092773) prior art reference. On appeal, the Applicant presented his arguments as to why the Examiner’s assertion was incorrect. The Applicant, however, provided no other evidence, such as affidavits, extrinsic evidence, etc.

What does the law say about an inherency rejection and the burden of proof?

When the claimed and prior art products are identical or substantially identical, or are produced by identical or substantially identical processes, the PTO can require an applicant to prove that the prior art products do not necessarily or inherently possess the characteristics of his claimed product. See In re Ludtke, [441 F.2d 660 (CCPA 1971)]. Whether the rejection is based on “inherency” under 35 U.S.C. § 102, on “prima facie obviousness” under 35 U.S.C. § 103, jointly or alternatively, the burden of proof is the same, and its fairness is evidenced by the PTO’s inability to manufacture products or to obtain and compare prior art products. See In re Brown, 459 F.2d 531. . . ([CCPA]1972). In re Best, 562 F.2d 1252, 1255 (CCPA 1977).

The applicant has the burden of coming forward with evidence in rebuttal, when the prior art includes a method that appears, on its face, to be capable of producing the claimed composition. This burden may be met by presenting sufficient reason or authority or evidence, on the facts of the case, to show that the prior art method would not produce or would not be expected to produce the claimed subject matter. In re Kumar, 418 F.3d 1361, 1368 (Fed. Cir. 2005).

In Ex parte Zechlin, the Examiner presented a legitimate inherency rejection and the Applicant responded using only “attorney argument” and did not present any 1.132 affidavits, references to text books, scientific treatises, etc. That was a bad move by the Applicant’s attorney, since he carried the burden of proving the inherency rejection was not accurate. As a result, the Board in Ex parte Zechlin found the Applicant did not meet his burden in rebutting the Examiner’s finding of inherency.

Lessons Learned: The moral of the story here is that once the Examiner makes a finding of inherency, the burden is moved to the Applicant to properly rebut the Examiner’s finding. And it’s a high burden. You wont get off with a few paragraphs of attorney argument. In order to properly rebut a finding of inherency, the patent practitioner should err on the side of caution and get a professor or credited engineer to provide a 1.132 affidavit and/or provide a good bibliography of textbooks, scientific journals and academic articles that support his position.


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