In Sanofi-Aventis v. Pfizer Inc., No. 12-1345 (Fed. Cir. Nov. 5, 2013), the Federal Circuit affirmed the Board's award of priority of invention to Pfizer Inc. ("Pfizer") based on an interference count to an isolated polynucleotide cDNA encoding the human interleukin-13 receptor binding chain ("IL-13bc").

Both Pfizer and Sanofi-Aventis ("Sanofi") were conducting research on IL-13, a regulatory molecule called a cytokine, and both discovered and filed patent applications directed to the polynucleotide encoding the relevant binding chain, IL-13bc. During an interference proceeding, Sanofi was awarded the benefit of its December 6, 1995, priority date. Pfizer's earliest filing date was March 1, 1996, but Pfizer presented documentary and testimonial evidence that it had isolated and identified the desired cDNA before Sanofi's benefit date. Specifically, Pfizer presented evidence that its scientists had isolated full-length human IL-13bc from a human cDNA library by October 16, 1995, and had confirmed its identity by October 25, 1995. However, due to sequencing errors, Pfizer's analysis was in error as to eight of IL-13bc's 1143 nucleotides. Pfizer corrected its sequence analysis by February 7, 1996, after Sanofi's benefit date.

The Board awarded priority of invention to Pfizer, concluding that Pfizer had established conception of the subject matter of the count when it selected, isolated, and obtained the desired full-length IL-13bc cDNA and verified it as the desired product. The Board rejected Sanofi's argument that Pfizer could not establish conception as a matter of law until Pfizer had the full and correct nucleotide sequence of
IL-13bc. The Board disagreed with Sanofi's reading of Federal Circuit precedent, including Amgen Inc. v. Chugai Pharmaceutical Co., 927 F.2d 1200 (Fed. Cir. 1991); Fiers v. Revel, 984 F.2d 1164 (Fed. Cir. 1993); and Burroughs Wellcome Co. v. Barr Laboratories, Inc., 40 F.3d 1223 (Fed. Cir. 1994). According to the Board, in this precedent, the issue was not identification of the operative DNA by full nucleotide analysis, but rather isolation of the operative DNA and identification of that DNA by whatever characteristics sufficiently distinguished it. Sanofi appealed.

"When the subject matter is a DNA segment, conception requires possession and appreciation of the DNA segment that is claimed." Slip op. at 9.

The Federal Circuit affirmed the Board's priority decision. The Court held that, contrary to Sanofi's reading of the Court's precedent, "when 'an inventor is unable to envision the detailed constitution of a gene' there may nonetheless be conception and reduction to practice of the gene when the inventor is in possession of the gene and a method of preparation, i.e. 'after the gene has been isolated,' accompanied by knowledge of 'other characteristics sufficient to distinguish it from other genes.'" Slip op. at 6-7 (quoting Amgen, 927 F.2d at 1206). And, according to the Court, Pfizer's activity of isolating and identifying the IL-13bc cDNA met these criteria.

The Court further observed that precedent illustrates a variety of circumstances in which conception and reduction to practice were met for biological molecules although the complete sequence was not known. Specifically, the Court pointed to Enzo Biochem, Inc. v. Gen-Probe Inc., 323 F.3d 956 (Fed. Cir. 2002), which upheld claims for deposited DNA probes although the nucleotide sequences had not been determined; University of New Mexico v. Knight, 321 F.3d 1111 (Fed. Cir. 2003), which explained that a chemical structure is simply a means of describing a compound and not the invention itself; and
In re Wallach, 378 F.3d 1330 (Fed. Cir. 2004), which held that the inventors were in possession of a protein when the protein was described by a partial amino acid sequence in addition to other characteristics sufficient to identify it.

Accordingly, the Court held that not only were the Board's unchallenged factual findings supported by substantial evidence, but also the Board had "correctly based conception and reduction to practice on the possession of the isolated DNA segment that was shown to have the desired properties." Slip op. at 9. The Court thus affirmed the Board's award of priority to Pfizer.

Judges: Newman (author), Lourie, Davis (sitting by designation)

[Appealed from Board]

*Yieyie Yang is a Law Clerk at Finnegan.

This article previously appeared in Last Month at the Federal Circuit, December 2013.

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