Reviewing Factual Findings for Clear Error, Teva's Patent Still Indefinite: Federal Circuit | Practical Law

Reviewing Factual Findings for Clear Error, Teva's Patent Still Indefinite: Federal Circuit | Practical Law

In Teva Pharmaceuticals USA, Inc. v. Sandoz Inc., the US Court of Appeals for the Federal Circuit, reviewing the district court's subsidiary claim construction fact findings for clear error, again found that the term "molecular weight" was indefinite.

Reviewing Factual Findings for Clear Error, Teva's Patent Still Indefinite: Federal Circuit

by Practical Law Intellectual Property & Technology
Published on 19 Jun 2015 • USA (National/Federal)
In Teva Pharmaceuticals USA, Inc. v. Sandoz Inc., the US Court of Appeals for the Federal Circuit, reviewing the district court's subsidiary claim construction fact findings for clear error, again found that the term "molecular weight" was indefinite.
On June 18, 2015, in Teva Pharmaceuticals USA, Inc. v. Sandoz, Inc., the US Court of Appeals for the Federal Circuit, on remand from the US Supreme Court, reviewed the district court's factual findings concerning claim construction for clear error (Nos. 2012-1567, 2012-1568, 2012-1569, 2012-1570, (Fed. Cir. June 18, 2015)). The court found no error in the US District Court for the Southern District of New York's factual findings, but again reversed the district court and held that the term "molecular weight" in US Patent No. 5,800,808 is indefinite as a matter of law.
After the Supreme Court held that the Federal Circuit must apply a clear error standard of review when reviewing a district court's factual findings made during claim construction, it remanded the case to allow the Federal Circuit to consider whether any of the district court's factual findings were clearly erroneous. For more information on the Supreme Court's decision, see Legal Update, Supreme Court: Facts Underlying Claim Construction Must Be Reviewed for Clear Error.
On remand, the Federal Circuit held that the term "molecular weight" is indefinite, explaining that:
  • The parties agreed that the term molecular weight could mean either:
    • peak average molecular weight (Mp);
    • number average molecular weight (Mn); or
    • weight average molecular weight (Mw).
  • The claim and specification do not specify which measure of molecular weight to use, and in a typical product sample, Mp, Mn and Mw have different values.
  • There was no clear error in the district court's factual finding that a skilled artisan would understand that a chromatogram in the patent specification used peak average molecular weight.
  • The meaning of the term molecular weight in light of the patent, specification and knowledge of skilled artisans is a question of law. The court explained that a district court can properly make factual findings about how skilled artisans would understand disputed terms at the relevant time and these findings will be reviewed for clear error. However, the ultimate legal question about how a skilled artisan would view the term in light of all the evidence is a question of law. The court explained that Teva cannot transform the legal analysis about the meaning or significance of the intrinsic evidence into a fact question simply by having an expert opine on this issue.
  • The court reaffirmed that statements during the prosecution of subsequent patents are relevant to the meaning of similar claim terms in earlier issued patents, and relied on the applicant's inconsistent usage of the disputed term in later applications to support its finding that the term is indefinite.
Circuit Judge Mayer dissented and argued that the majority decision failed to give proper deference to the district court's factual findings.