Board Again Reverses An Obviousness Rejection For Examiner's Failure To Provide Adequate Rationale For Substituting Substances Having Different Functions

In Ex parte Fulton (Appeal 2011-001486, in U.S. Serial No. 10/839,112), involving an application which was on its third appeal, the BPAI overturned an examiner’s finding of obviousness on a claim to a method of marking a biopsy cavity inserting a bioresorbable body, comprising cellulose, into a lesion at the biopsy site. 

The examiner argued that the primary reference taught every claim element, including the bioresorbable body, but that it did not teach that the bioresorbable body comprised cellulose.  The examiner then relied on a second reference for its teaching of a cellulose biodegradable radiopaque marker, and a third reference for its teaching of a dehydrated cellulose which can expand to fill a body cavity (ear canal).

The Applicant-Appellant argued that a person of ordinary skill in the art likely would not have modified the primary reference to use cellulose, as in the second reference, to replace a metal coil in the primary reference.  They argued that merely because a material is known does not make it obvious to substitute for another when it is not disclosed to perform the same function as the material it is replacing.  Furthermore, they argued that the examiner had not articulated a specific rationale for modifying the primary (and second) reference in view of the third reference.

The Board emphasized that

[u]nder § 103, ‘there must be some articulated reasoning with some rational underpinning to support the legal conclusion of obviousness,’ (KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 418 (2007)),

and that

[o]bviousness is determined on the basis of the evidence as a whole and the relative persuasiveness of the arguments (In re Oetiker, 977 F.2d 1443, 1445 (Fed. Cir. 1992)).

The Board carefully considered the argument that the cellulose of the second reference did not function in the same manner as the coil spring marker of the primary reference.  Cognizant of the claim recitation of “inserting the bioresobable body into the biopsy site to mark the location of the biopsy site,” the Board noted that the primary reference’s device defined the margins of a lesion during extraction, preferably taking a helical shape to surround the lesion or forming beads or pellets deployed around the lesion.  The Board found that the second reference’s device was used to visualize the passage and placement of an endoprosthesis in a damaged artery or body lumen, and was not deployed around a lesion for biopsy.

While the third reference describes a cellulose wick for placement in the ear canal, the Board agreed that the examiner had not articulated a specific rationale for modifying the primary and second reference’s devices by the features of the third reference’s device.  Specifically, they found that the third reference provided no reason to meet the limitation of filling the biopsy site as in the primary reference, which would surround with marker, not fill with marker.

The Board then concluded that the fact that the cellulose of the second reference did not function in the same manner as the coil spring marker of the primary reference (surrounding a biopsy site versus filling it), and that the third reference provided no reason to modify the second reference to meet the claims.  Therefore, the Board found that the cited references did not support a finding of obviousness.

Thus, while the manner in which the elements function generally does not distinguish them from differently functioning elements in composition or article claims, in applications directed to methods, the function of the elements in the prior art can be relevant to overcoming an examiner’s finding of obviousness.