PTAB Holds Patent Eligible for Post-Grant Review After Petitioner Successfully Demonstrates that Patent Is Not Entitled to Earliest Claimed Priority Date

Sep 12, 2016

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Under the America Invents Act, PGR is available only for patents that have “at least one claim with an effective filing date on or after March 16, 2013, with ‘effective filing date’ having the definition given to it by 35 U.S.C. § 100(i).” If the effective filing date is prior to March 16, 2013, then the patent is ineligible for PGR. According to 35 U.S.C. § 100(i), the effective filing date is the filing date of the earliest application for which the patented invention is entitled. In instances when a patent is not entitled to any earlier filing date or right of priority, the effective filing date is the filing date of the patent itself. Id. 35 U.S.C. § 100(i).

The parties here disputed the effective filing date of the ’017 patent. The patent owner argued that the ’017 patent was entitled to the benefit of a series of earlier applications, the earliest of which was filed on October 25, 2002. Conversely, petitioner argued that the ’017 patent was not entitled to such benefit and that the effective filing date was March 24, 2014 (i.e., the filing date of the ’017 patent itself). The PTAB agreed with petitioner. Specifically, the PTAB found that all challenged claims require: (1) a heat transfer composition with a low toxicity refrigerant that essentially consists of 2,3,3,3-tetrafluorpropene (HFO-1234yf); (2) a lubricant that consists essentially of polyalkylene glycol(s) (PAG); and (3) a specific heat transfer application—automobile air conditioning. In reaching its determination, the PTAB noted that the earlier filed applications disclosed “blazemarks” to the general use of tetrafluorpropene and PAG lubricants and a “single passing reference” to automobile air conditioning.  However, that was insufficient.  Instead, the PTAB concluded that the earlier filed applications did “not enable the subject matter recited in [the challenged claims]” and failed to “provide sufficient guidance to demonstrate possession of the claimed subject matter as a whole, i.e., the combination of HFO-1234yf and [PAG] lubricant for automobile air conditioning.” Accordingly, the PTAB held that the ’017 patent had an effective filing date of March 26, 2014 and was thus eligible for PGR.

In the event that the ’017 patent was deemed ineligible for PGR, petitioner had also filed an inter partes review petition concurrent with its PGR petition. In view of the above determination, petitioner’s inter partes review petition was denied.

Arkema Inc., et al. v. Honeywell Intl. Inc., Case Nos. PGR2016-00011, Paper No. 13, PGR2016-00012, Paper No. 13, and IPR2016-00643, Paper No. 11 (PTAB, Sep. 2, 2016).

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