PTAB

IPR2016-00452

Daikin Industries Ltd v. Chemours Co FC LLC

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Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Compositions Comprising 3,3,3-Trifluoropropyne
  • Brief Description: The ’709 patent discloses compositions comprising the refrigerant HFO-1234yf that also contain small amounts (less than one weight percent) of certain specified impurities, referred to as "additional compounds." The patent asserts that these compounds are present as byproducts from the manufacturing process of HFO-1234yf.

3. Grounds for Unpatentability

Ground 1: Claims 1-4, 7, and 8 are obvious over Miller in view of the ARI 2006 Standard.

  • Prior Art Relied Upon: Miller (Application # 2007/0100175) and the ARI 2006 Standard (“2006 Standard for Specifications for Fluorocarbon Refrigerants: Standard 700”).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that the claimed compositions are the inherent and predictable result of following known prior art methods to produce a commercially acceptable refrigerant. Miller disclosed a detailed method for synthesizing HFO-1234yf via dehydrofluorination of HFC-245cb, resulting in a crude product with a purity of 91.3 area% (Example 1) and containing various impurities. The ARI 2006 Standard, a publicly accessible industry guide, established the purity requirements for fluorocarbon refrigerants, indicating a general industry expectation for a purity of at least 99.5% by weight. Petitioner contended that purifying the crude HFO-1234yf product from Miller using conventional distillation to meet the purity levels taught by the ARI 2006 Standard would inherently result in a final composition falling within the scope of the challenged claims.
    • To prove this inherency, Petitioner's expert physically replicated the synthesis process from Miller's Example 1 and then distilled the resulting crude product to a purity of over 99.5%. The final purified product was shown to contain HFO-1234yf along with 3,3,3-trifluoropropyne, E-HFO-1234ze, and HFO-1243zf, with the total amount of these "additional compounds" being less than one weight percent, thereby meeting all limitations of the narrowest challenged claims (3 and 8).
    • Motivation to Combine: Petitioner asserted that by the critical date, HFO-1234yf was widely recognized as a promising, environmentally friendly refrigerant with low global warming potential. A person of ordinary skill in the art (POSITA) would have been motivated to develop a commercially viable, industrial-scale manufacturing process for it. The high-yield synthesis method in Miller's Example 1 provided a suitable starting point. To make the resulting HFO-1234yf commercially acceptable, the POSITA would have been motivated to purify it to meet industry-accepted standards, such as the 99.5% purity level established in the ARI 2006 Standard for similar fluorocarbon refrigerants.
    • Expectation of Success: A POSITA would have had a reasonable expectation of success in combining these references. Synthesizing HFO-1234yf according to Miller's established catalytic process and subsequently purifying it via conventional distillation are routine and predictable procedures in chemical engineering. The successful purification of a crude chemical mixture to a target purity level was well within the ordinary skill in the art.
    • Key Aspects: The central thrust of Petitioner's argument rested on inherency, supported by an actual physical reproduction of the combined teachings of the prior art. Petitioner also dedicated significant argument to establishing that the ARI 2006 Standard was a publicly accessible "printed publication" before the patent's critical date, citing its availability on the ARI website (verified through an Internet Archive affidavit), a copyright notice of 2006, and its purpose as an industry guidance document.

4. Key Claim Construction Positions

  • "HFC-245cb": Claims 1 and 7 recite "HFC-245cb" in a list of possible additional compounds, but the ’709 patent specification does not define the code. Petitioner proposed construing it based on the Miller reference to mean 1,1,1,2,2-pentafluoropropane (CF3CF2CH3), which is the starting material used to produce HFO-1234yf in Miller.
  • "HFO-1234ze": Claims 4 and 8 require the presence of "HFO-1234ze." Petitioner argued this term should be construed according to the patent's specification as "E- or Z-1,3,3,3-tetrafluoropropene," referring to the trans and cis isomers of the compound, respectively.
  • "greater than zero weight percent" and "less than one weight percent": Petitioner asserted that a POSITA would understand these phrases, which define the total amount of "additional compounds," to mean a weight percentage relative to the total weight of the entire composition.

5. Relief Requested

  • Petitioner requested institution of an inter partes review and cancellation of claims 1-4, 7, and 8 of the ’709 patent as unpatentable under 35 U.S.C. §103.