A small increase in a Prior Art’s taught range needs to have sufficient reason for the modification to establish obviousness under 35 U.S.C. §103
| August 6, 2021
Chemours Co. FC, LLC vs Daikin Ind., LTD
Decided on July 22, 2021
NEWMAN, DYK, and REYNA. Opinion by Reyna. Concurring and Dissenting in part by Dyk.
Summary:
Chemours Company FC, LLC, appealed the final written decisions of the Patent Trial and Appeal Board from two inter partes reviews brought by Daikan Industries, Ltd. Chemours argued on appeal that the Board erred in its obviousness factual findings and did not provide adequate support for its analysis of objective indicia of nonobviousness. The CAFC found that the Board’s decision on obviousness was not supported by substantial evidence and that the Board erred in its analysis of objective indicia of nonobviousness. Consequently, they reversed the Board’s decision.
Background:
Chemours Company FC, LLC, appealed the final written decisions of the Patent Trial and Appeal Board from two inter partes reviews brought by Daikan Industries, Ltd., et al. Chemours argues on appeal that the Board erred in its obviousness factual findings and did not provide adequate support for its analysis of objective indicia of nonobviousness.
Two patents were at issue. U.S. Patent No. 7,122,609 (the “’609 patent) and U.S. Patent No. 8,076,4312 (the “’431 patent”). The representative ’609 patent relates to a unique polymer for insulating communication cables formed by pulling wires through melted polymer to coat and insulate the wires, a process known as “extrusion.”
Claim 1 of the ’609 patent is representative of the issues on appeal:
1. A partially-crystalline copolymer comprising tetrafluoroethylene, hexafluoropropylene in an amount corresponding to a hexafluoropropylene index (HFPl) of from about 2.8 to 5.3, said copolymer being polymerized and isolated in the absence of added alkali metal salt, having a melt flow rate of within the range of about 30±3 g/10 min, and having no more than about 50 unstable end groups/106 carbon atoms.
The Board found all challenged claims of the ’609 patent and the ’431 patent to be unpatentable as obvious in view of U.S. Patent No. 6,541,588 (“Kaulbach”).
On appeal, Chemours argued that Daikin did not meet its burden of proof because it failed to show that a person of ordinary skill in the art (“POSA”) would modify Kaulbach’s polymer to achieve the claimed invention.
The Kaulbach reference teaches a polymer for wire and cable coatings that can be processed at higher speeds and at higher temperatures. Kaulbach highlights that the polymer of the invention has a “very narrow molecular weight distribution.” Kaulbach discovered that prior beliefs that polymers in high-speed extrusion application needed broad molecular weight distributions were incorrect because “a narrow molecular weight distribution performs better.” In order to achieve a narrower range, Kaulbach reduced the concentration of heavy metals such as iron, nickel and chromium in the polymer.
In the Kaulbach example relied on by the Board, Sample A11, Kaulbach’s melt flow rate is 24 g/10 min, while the claimed rate of Claim 1 of the ‘609 patent is 30±3 g/10 min.
The Board found that Kaulbach’s melt flow rate range fully encompassed the claimed range, and that a skilled artisan would have been motivated to increase the melt flow rate of Kaulbach’s preferred embodiment to within the claimed range to coat wires faster. Specifically, the Board found:
We also are persuaded that the skilled artisan would have been motivated to increase the [melt flow rate] of Kaulbach’s Sample A11 to be within the recited range in order to achieve higher processing speeds, because the evidence of record teaches that achieving such speeds may be possible by increasing a [polymer’s] [melt flow rate].
In addition, the Board found that the portions of Kaulbach’s disclosure lacked specificity regarding what is deemed “narrow” and “broad,” and that it would have been obvious to “broaden” the molecular weight distribution of the claimed polymer.
Second, Chemours argued that the Board legally erred in its analysis of objective indicia of nonobviousness by showings of commercial success finding an insufficient nexus between the claimed invention and Chemours’s commercial polymer, as the Board required market share evidence to show commercial success.
CAFC Decision:
- Obviousness and teaching away
The CAFC found that the Board ignored the express disclosure in Kaulbach that teaches away from the claimed invention and relied on teachings from other references that were not concerned with the particular problems Kaulbach sought to solve. In other words, the Board did not adequately grapple with why a skilled artisan would find it obvious to increase Kaulbach’s melt flow rate to the claimed range while retaining its critical “very narrow molecular-weight distribution.”
The Court maintained that the Board’s reasoning does not explain why a POSA would be motivated to increase Kaulbach’s melt flow rate to the claimed range, when doing so would necessarily involve altering the inventive concept of a narrow molecular weight distribution polymer. The Court held that this is particularly true in light of the fact that the Kaulbach reference appears to teach away from broadening molecular weight distribution and the known methods for increasing melt flow rate.
Specifically, Kaulbach includes numerous examples of processing techniques that are typically used to increase melt flow rate, which Kaulbach cautions should not be used due to the risk of obtaining a broader molecular weight distribution.
These factors do not demonstrate that a POSA would have had a “reason to attempt” to get within the claimed range, as is required to make such an obviousness finding.
As Chemours persuasively argues, the Board needed competent proof showing a skilled artisan would have been motivated to, and reasonably expected to be able to, increase the melt flow rate of Kaulbach’s polymer to the claimed range when all known methods for doing so would go against Kaulbach’s invention by broadening molecular weight distribution.
The CAFC therefore held that the Board relied on an inadequate evidentiary basis and failed to articulate a satisfactory explanation that is based on substantial evidence for why a POSA would have been motivated to increase Kaulbach’s melt flow rate to the claimed range, when doing so would necessarily involve altering the inventive concept of a narrow molecular weight distribution polymer.
- Commercial success
In addition, Chemours argued that the Board legally erred in its analysis of objective indicia of nonobviousness finding an insufficient nexus between the claimed invention and Chemours’s commercial polymer, and its requirement of market share evidence to show commercial success.
Specifically, Chemours argued that the Board improperly rejected an extensive showing of commercial success by finding no nexus on a limitation-by-limitation basis, rather than the invention as a whole. Chemours contended that the novel combination of these properties drove the commercial success of Chemours’s commercial polymer. Second, Chemours argued the Board improperly required Chemours to proffer market share data to show commercial success.
The CAFC held that contrary to the Board’s decision, the separate disclosure of individual limitations, where the invention is a unique combination of three interdependent properties, does not negate a nexus. The Court recognized that concluding otherwise would mean that nexus could never exist where the claimed invention is a unique combination of known elements from the prior art.
Further, the Court held, quoting prior caselaw, that the Board, erred in its analysis that gross sales figures, absent market share data, “are inadequate to establish commercial success.”
“When a patentee can demonstrate commercial success, usually shown by significant sales in a relevant market, and that the successful product is the invention disclosed and claimed in the patent, it is presumed that the commercial success is due to the patented invention.” J.T. Eaton & Co. v. Atl. Paste & Glue Co., 106 F.3d 1563, 1571 (Fed. Cir. 1997); WBIP, 829 F.3d at 1329. However, market share data, though potentially useful, is not required to show commercial success. See Tec Air, Inc. v. Denso Mfg. Mich. Inc., 192 F.3d 1353, 1360–61 (Fed. Cir. 1999).
The CAFC therefore reversed the Board’s finding of obviousness of the ‘609 and ‘431 claims at issue.
- Dissent
Judge Dyk dissented in part as to the strength of the teaching away by Kaulback. Specifically, he noted that Kaulbach’s copolymer is nearly identical to the polymer disclosed by claim 1 of the ’609 patent. The only material difference between claim 1 and Kaulbach is that Kaulbach discloses (in Sample A11) a melt flow rate of 24 g/10 min, slightly lower than 27 g/10 min, the lower bound of the 30 ± 3 g/10 min rate claimed in claim 1 of the ’609 patent.
As to the teachings of Kaulbach, he went on to note that even though Kaulbach determined that “a narrow molecular weight distribution performs better,” it expressly acknowledged the feasibility of using a broad molecular weight distribution to create polymers for high speed extrusion coating of wires. Hence, Judge Dyk concluded that this is not a teaching away from the use of a higher molecular weight distribution polymer.
Contrary to the majority’s assertion, modifying the molecular weight distribution of Kaulbach’s disclosure of a 24 g/10 min melt flow rate to achieve the 27 g/10 min melt flow rate of claim 1 would hardly “destroy the basic objective” of Kaulbach as the majority claims.
Take away
- There must be clear motivation for a POSA to modify a claimed range even to a small extent. Evidence within the prior art that such a modification would not be beneficial maybe a sufficient teaching away and can negate a finding of increasing the range as an obvious modification. Patent prosecutors should be more assertive in requiring a clear showing of reasons to make a modification of increasing a range outside of a prior art’s taught range.
