Obviousness Allegations Fall Short After Petitioner's "Weak Showing" Of A Motivation To Combine The Art

Published date09 December 2022
Subject MatterIntellectual Property, Patent
Law FirmFinnegan, Henderson, Farabow, Garrett & Dunner, LLP
AuthorMr Jameson Gardner and Stacy Lewis


In the decisions for parallel IPRs concerning challenges to claims of a single patent, both captioned Laboratory Corporation of America Holdings v. Ravgen, Inc.,1,[2] the Patent Trial & Appeal Board ("the Board") found none of the challenged claims unpatentable, determining that Petitioner LabCorp failed to prove that the claims were obvious over the prior art. Instead, the Board determined that a person having ordinary skill in the art ("POSA") would have been dissuaded from combining the teachings of the cited references.


Petitioner LabCorp filed two IPR petitions challenging Patent Owner Ravgen's U.S. Patent No. 7,332,277 B2 ("the '277 patent"). The '277 patent is directed to non-invasive methods for DNA sampling and detection of genetic disorders in a fetus through the analysis of cell-free fetal DNA ("cffDNA"). A key element of the challenged claims was a limitation requiring the inhibition of cell lysis in a sample to increase the proportion of cffDNA in the sample relative to maternal DNA.3 Petitioner argued that the challenged claims of the '277 patent would have been unpatentable on obviousness grounds over various combinations of the references Chiu, Lo, Bianchi, Granger, and Rao.

PTAB Decisions

The Board held that Petitioner failed to show that the claims of the '277 patent were obvious over the cited prior art. Specifically, the Board noted that Petitioner failed to establish that a POSA would have been motivated to combine the teachings of the prior art and found instead that a POSA would have been dissuaded from combining the teachings of the cited references.


Petitioner alleged in IPR 2021-00902 that the challenged claims would have been obvious over Chiu and Bianchi; Chiu, Bianchi, and Granger; or Chiu and Rao. Id. at *4-5. Chiu relates to the effects of different blood processing protocols on the quantification of cell-free DNA in maternal plasma but does not teach a method of preventing cell lysis in the analysis of cell-free DNA. Id. at *17-20. Petitioner alleged that this deficiency was remedied by the teachings of Bianchi, Granger, and Rao.

Petitioner argued that Bianchi, Granger, and Rao all teach the use of paraformaldehyde ("PFA") to stabilize or fix cells within a sample and therefore prevent cell lysis. Patent Owner argued that Bianchi, Granger, and Rao taught that PFA was used to both permeabilize and fix cells for measurement and analysis within a sample. Importantly, permeabilization of a cell membrane would provide routes for cellular contents...

To continue reading

Request your trial

VLEX uses login cookies to provide you with a better browsing experience. If you click on 'Accept' or continue browsing this site we consider that you accept our cookie policy. ACCEPT