Federal Circuit Decision will not Interfere with Interference

On November 5, 2013 the US Court of Appeals for the Federal Circuit handed down a decision in Sanofi-Aventis v. Pfizer Inc., 108 USPQ2d 1741.  The decision is of interest because it had the potential to directly deal with the question of the patentability of biomolecules such as DNA and drug targets.  However, the Court prudently exercised restraint in not doing so.

Decisions on complex, and often emotionally-charged, patent issues have become increasingly common over the past several years, and have been widely followed in the popular press.  Just this summer, the Supreme Court rendered a decision in a patent case involving a diagnostic test for determining the risk for breast and ovarian cancers.  See Association for Molecular Pathology v. Myriad Genetics, Inc., 133 S. Ct. 2107 (2013).  In Myriad, the Supreme Court pronounced that DNA is not patent eligible subject matter, but that synthetically created complementary DNA (cDNA) is.  It is important to note that none of Myriad’s diagnostic method claims were actually before the Court.  Decisions such as Myriad are now being cited by the Federal Circuit and other courts in rendering opinions of significance to the biotech and pharmaceutical industries.

The Pfizer case stems from a patent interference decided by the U.S. Patent and Trademark Office, Board of Patent Appeals and Interferences (the “Board”).  A patent interference is a complex administrative proceeding to determine which party has the earlier right to a patent.  Interference proceedings are unique to US Patent Law, because up until very recently, US patents were awarded on a first-to-invent, rather than a first-to-file, basis (as in most other countries).  In the US, a party with a later-filed patent application (the “junior party” in interference parlance) can actually prevail over a party with an earlier patent application (the “senior party”) if they can demonstrate an earlier invention date.  This has now all changed.  The America Invents Act of 2011 established a first-to-file system, putting the US in alignment with the rest of the world.  However, interference practice will be with us for some time, because patent applications filed under the old law can still be challenged in an interference proceeding.

The central question in Pfizer is whether Pfizer (the junior party) established conception and reduction to practice for a nucleotide sequence for a human interleukin-13 receptor before the senior party, Sanofi.  The Board had originally awarded Pfizer priority of invention.  Sanofi appealed the decision to the Federal Circuit (interferences are appealed directly from the Board to the Federal Circuit rather than first to a District Court).  The facts underlying the case are interesting.  Both Pfizer and Sanofi were conducting research relating to the IL-13 receptor and had both filed patent applications with claims directed to the polynucleotide (i.e. the cDNA) encoding it.  Sanofi had a filing date of December 6, 1995.  Pfizer had a filing date of March 1, 1996.  In the interference proceeding, Pfizer presented documentary and testimonial evidence that it had isolated and identified the nucleotide prior to Sanofi’s filing date.  However, here is where things get interesting.  Pfizer’s original nucleotide sequence contained sequencing errors in eight of the 1143 nucleotides.  These errors were not corrected until February 7, 1996.  Sanofi therefore argued that Pfizer’s cDNA could not establish priority of invention until the errors were corrected, which was not until after Sanofi’s filing date.  Pfizer, however, presented evidence that its initial sequence was 99.3% accurate, that minor sequencing errors were common and routinely corrected, and that it had after all actually isolated and obtained the operative DNA.  The Federal Circuit thus narrowed down the issue before it to whether Pfizer’s “conception [of the invention] is negated because the nucleotide sequence was not corrected until after the Sanofi benefit date of December 6, 1995”.  In rendering its decision, the Court provided a detailed and well-reasoned analysis of the case law on conception and reduction to practice.  The Court affirmed the Board decision agreeing that “Pfizer had successfully searched for and isolated” the IL-13bc DNA segment, and possessed and appreciated [it]” before Sanofi.

This appeal could have been an opportunity for the Federal Circuit to further expound on the patentability of DNA.  In first learning about this Federal Circuit decision, I was expecting at least some reference to the recent Myriad case, even if only in passing or with a comment why the Court was not going to examine a DNA patentability question not strictly before it.  However, the Court wisely demonstrated the proper restraint and avoided complicating the matter.  The Federal Circuit did not interfere with this interference.


–  Anthony D. Sabatelli, PhD, JD
Check out Anthony’s bio page


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