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Fed. Circ. Affirms PTAB Finding that Gas Furnace Patent Claims Are Unpatentable
March 18, 2016

The Federal Circuit recently affirmed a PTAB finding in IPR2014-00219 that claims 1-6 of U.S. Patent No. 6,222,719(“the ’719 patent”) are unpatentable as obvious.

The ’719 patent is directed to a control circuit for a gas furnace and an electronic ignition for gas burners. Claim 1, the only independent claim of the six challenged, recites an “igniter circuit” which “actuate[s]” or starts, a furnace gas burner through a “pulsating current [being] applied to a coil.”

The PTAB issued a Final Written Decision on April 1, 2015, finding claims 1-6 to be obvious over the combination of prior art patents Courier (U.S. Patent No. 4,167,767) and Potts (U.S. Patent No. 3,514,240).

The Board found that the references collectively disclosed all elements of claim 1, that expert testimony provided an “articulated reasoning with rational underpinning” to combine the references, and that an unrefuted statement by the Examiner during original prosecution supported the conclusion that a person of ordinary skill in the art would have been “motivated to pursue a voltage doubling circuit to increase the amount of voltage accumulated.” The Board also found the Patent Owner’s bodily incorporation argument, which hinged on an AC/DC circuit power supply distinction, to be without merit, stating that “[t]he test for obviousness is not whether the features of a secondary reference may be incorporated bodily into the structure of the primary reference.”

The court subsequently found claims 2-6 similarly unpatentable as the Patent Owner had “not asserted that limitations of dependent claims 2- 6 further distinguish over the combination of Courier and Potts.”

In a Rule 36 judgment, Judges Lourie, Bryson, and Reyna affirmed the PTAB’s determinations.

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