United States: Federal Circuit Finds Solvay HFC Patent Invalid Under 102(g)

In Solvay S.A. v. Honeywell International Inc., the Federal Circuit upheld the district court's finding that Solavay's HFC patent was invalid under 35 USC § 102(g). Although the impact of this case may be muted by the first-inventor-to-file provisions of the America Invents Act (AIA), the "secret prior art" provisions of § 102(g) will remain relevant for most patents with a priority date earlier than March 16, 2013.

The Patent at Issue

The patent at issue was Solvay's U.S. Patent 6,730,817, directed to an improved method for making hydrofluorocarbon HFC-245fa, which is a non-ozone-depleting hydrofluorocarbon (HFC). Claim 1 was the only claim at issue on appeal:

1. In a process for the preparation of 1,1,1,3,3-pentafluoropropane comprising reaction of 1,1,1,3,3-pentachloropropane with hydrogen fluoride in the presence of a hydrofluorination catalyst, the improvement which comprises carrying out the reaction at a temperature and under a pressure at which 1,1,1,3,3-pentafluoropropane is gaseous and isolating and 1,1,1,3,3-pentafluoropropane from the reaction mixture by drawing off 1,1,1,3,3-pentafluoropropane and hydrogen chloride in a gaseous phase as each of said 1,1,1,3,3-pentafluoropropane and hydrogen chloride is being formed.

The patent was granted May 4, 2004, and claims priority to a French application filed October 23, 1995.

The Secret Prior Art

The Federal Circuit decision describes the secret prior art as arising from work done in Russia by the Russian Scientific Center for Applied Chemistry (RSCAC) and reduced to practice in the U.S. by Honeywell before Solvay's October 1995 priority date.

As summarized in the Federal Circuit opinion, the RSCAC entered into a research agreement in 1994, pursuant to which the "RSCAC engineers, working in Russia, conducted process development studies for the commercial production of HFC-45fa." In July of 1994, the RSCAC sent a report to Honeywell "documenting the development of a continuous process capable of producing high yields of HFC-245fa by reacting HCC-240fa4 with hydrogen fluoride in the presence of a catalyst," and "Honeywell personnel in the United States used the RSCAC's report to run the same process in this country in 1995, before the '817 patent's October priority date."

Previous Proceedings

In the first round of litigation, the district court determined that the Solvay patent was invalid under § 102(g) because "the Honeywell engineers were other inventors who made the invention in this country without abandoning, suppressing, or concealing it." On appeal, the Federal Circuit reversed that finding because the Honeywell engineers "could not qualify as 'another inventor' because they 'did not conceive the invention ... but derived it from' ... the RSCAC engineers."

On the remand that led to this appeal, Honeywell argued that "the Russian inventors made the invention in this country by sending instructions to Honeywell personnel who used the instructions to reduce the invention to practice in this country." A jury agreed, and the district court again entered judgment against the '817 patent under the different § 102(g) theory.

The Federal Circuit Decision

The latest Federal Circuit decision is authored by Judge Dyk and joined by Chief Judge Rader. Judge Newman filed a dissenting opinion.

Section 102(g) provides in relevant part:

A person shall be entitled to a patent unless . . . before such person's invention thereof, the invention was made in this country by another inventor who had not abandoned, suppressed, or concealed it.

According to the Federal Circuit decision, Solvay did "not dispute that the Russians were first to conceive the invention recited in claim 1 or that Honeywell reduced it to practice in this country before Solvay's October 23, 1995, priority date, but challenges (1) the jury's finding of nonsuppression, and (2) the district court's ruling that the Russians made the invention in this country."

The finding of nonsuppression was based on a finding that the RSCAC had filed a Russian patent application directed to the process claimed in the '817 patent. Solvay challenged the claim construction that supported these findings, but the Federal Circuit determined that either Solvay had waived that argument or that the claim construction at issue was correct.

The finding that the Russians had made the invention in the U.S. was based on a finding that Honeywell's activities in the U.S. inured to the benefit of the RSCAC engineers. Solvay challenged this finding because "the RSCAC engineers did not expressly ask the Honeywell researchers to perform the inventive process."

The majority rejected Solvay's position:

[O]ur case law does not support Solvay's contention that an inventor must make an express directive or request to benefit from a third party's reduction to practice. Rather, inurement exists if the inventor authorizes another to reduce his invention to practice. Here, the research agreement between the RSCAC and Honeywell confirms that the RSCAC authorized Honeywell to practice its invention in the United States and contemplated that Honeywell would do so. .... The undisputed facts show that the RSCAC authorized Honeywell to practice its invention and specifically contemplated that it would do so under the companies' joint research agreement aimed at developing commercial processes for the production of HFC-245fa. The RSCAC engineers gave Honeywell personnel the information they needed to perform the inventive process in this country in July 1994, and Honeywell relied on that information in so doing.

The Federal Circuit concluded:

We therefore agree with the district court that the process invented by the Russian engineers was made in this country when Honeywell successfully performed the process because the Russians authorized Honeywell personnel to practice the invention and specifically contemplated that they would do so.

Thus, the court held the Solvay HFC patent invalid under 102(g).

Judge Newman's Dissent

Judge Newman filed a dissenting opinion charging the majority with "creat[ing] a new class of secret prior art, holding that a privately performed experiment, without publication or public knowledge or use or sale or inclusion in a United States patent application, is invalidating 'prior art.'"

In particular, Judge Newman criticizes the majority for applying the doctrine of "inurement" outside of the interference context, and for being inconsistent with the previous decision in this case, where the Federal Circuit held "that the Russian invention was conceived and reduced to practice in Russia, and that Honeywell's repetition of the process in the United States was not an invention made in the United States."

The Problem of Secret Prior Art

This case underscores the problem of secret prior art, and highlights why many welcomed the AIA changes to 35 USC § 102 that eliminated § 102(g) and focused the definition of prior art on what was "known to the public." In this case, neither Solvay, nor the Patent Office, nor anyone else other than the RSCAC and Honeywell could have known that Solvay was not the first to invent the subject matter at issue.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

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