On December 11, 2019, the PTAB designated two additional decisions as “informative.” Such informative decisions are not binding on subsequent panels, but are meant to provide guidance on recurring issues encountered by PTAB panels in post-grant proceedings. Here, both of the newly designated decisions—one a Decision on Institution and the other a Final Written Decision—provide guidance to petitioners on their obligation to set forth in the petition a well-developed rationale for combining prior art references as part of an obviousness combination.

In Johns Manville Corp. v. Knauf Insulation, Inc., IPR2018-00827, Paper 9 (October 16, 2018), the Board held the petitioner’s rationale for combining prior art references to be deficient for several reasons. First, the Board faulted the petitioner’s focus on establishing a prior art reference as “analogous art,” calling this merely a threshold inquiry. Paper 9 at 6-7. Mere compatibility of references is not sufficient to establish an obviousness conclusion. Petitioners must do more than demonstrate that a reference is analogous art or relevant to the field of endeavor of the challenged patent. Petitioners must establish that a skilled artisan would have reason to combine the reference’s teachings with other prior art in the manner set forth in the claims.

Second, the Board found that the petitioner failed to sufficiently explain which elements of the cited references could be predictably combined. “Petitioner indicates which of the references purportedly discloses each element of claim 1, but does not indicate which of the prior art elements allegedly has a known function, what that function is, and why that function is allegedly predictable.” Id. at 19. Petitioners must explain why a person of skill in the art would have selected a prior art element and explain why the combination of elements is predictable, and must do so with supporting evidence.

Third, the Board found the petitioner’s unsupported statements that combining the references would have been “well within the skill of a POSA” do not meet the petitioner’s burden. Id. at 19-20. Petitioner bears the burden to demonstrate that a skilled artisan would have been motivated to combine the teachings of the prior art references to achieve the claimed invention. Obviousness requires a reason that would have prompted a person of skill in the relevant field to combine the elements in the way the claimed invention does.

In a Final Written Decision in Hulu, LLC v. Sound View Innovations, LLC, IPR2018-00582, Paper 34 (August 5, 2019), the Board upheld the patentability of the challenged claims because the petitioner failed to show a sufficient rationale for combining the references. In response to the petitioner’s first ground of unpatentability, the patent owner set forth evidence during the trial phase that undercut the petitioner’s stated motivation for combining the prior art references. To rebut this, the petitioner provided additional argument that the primary reference could still function when combined with elements of secondary references. But petitioners must be mindful that obviousness concerns whether a skilled artisan not only could have made but would have been motivated to make the combinations or modifications of prior art to arrive at the claimed invention.

In sum, these two decisions, newly designated as informative by the PTAB, remind petitioners of the necessity to set forth in the petition a well-developed rationale for combining references. The rationale for combining references must be supported by evidence in the record.