Court Won't Restore Enzo's $61M DNA Test Patent Verdict

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By John T. Aquino

Feb. 24 — The $61 million DNA test patent infringement judgment in favor of Enzo Biochem won't be restored, a federal district court said Feb. 22.

Enzo had argued in the 12-year-old case that a ruling by the U.S. Court of Appeals for the Federal Circuit that a single claim wasn't infringed shouldn't affect the other claims-at-issue, so the jury verdict of infringement of the other claims should stand. But the U.S. District Court for the District of Connecticut found that the appeals court's infringement ruling, although a “cryptic mandate,” did apply to all of the contested claims.

Judge Janet Bond Arterton wrote, “It would be odd indeed for the Federal Circuit to continuously use the plural ‘claims' if it intended to refer only to claim 1.”

The district court granted judgment in favor of defendants Applera Corp., which became Life Technologies Corp., and Tropix Inc. Life Tech was acquired in 2014 by Thermo Fisher Scientific (TFS), which reports $17 billion in global revenues.

Enzo said in a Form 8-K filing submitted to the Securities and Exchange Commission on Feb. 24, “The Company believes this latest decision is in error and Enzo will therefore appeal the decision.”

Two Federal Circuit Reversals

Enzo and Yale University initiated the litigation in 2004, alleging that Applera and Tropix infringed six patents that cover techniques and processes for detecting the presence of DNA in a sample. Three of the patents—U.S. Patent Nos. 5,476,928, 5,449,767 and 5,328,824—disclose the invention of non-radioactive labeling and specify formation of a complex of hybrid nucleotides and a detectable polypeptide.

The district court favored Enzo's construction of the claims that the patents cover both direct and indirect detection and granted summary judgment in Enzo's favor.

The Federal Circuit reversed the district court's ruling in 2010, finding many of the claims of the patents invalid. Enzo then limited its litigation to claims 1, 8, 67, 68 and 70 of the '767 patent .

A jury returned a verdict that the defendants' products directly infringed and induced customers to infringe the claims-at-issue. On appeal, the Federal Circuit's analysis of claim 1 of the '767 patent, which it stated was “representative,” found the claim limited to indirect detection and that the district court had erred in construing the claim to cover both direct and indirect detection .

The appeals court reversed the district court's claim construction, vacated the court's finding of infringement and remanded the case to the district court to determine whether the accused product still infringed the claims-at-issue.

Thermo Fisher Scientific Interprets ‘Cryptic Message' Best

On remand, Arterton wrote that the parties both had attempted to reason through the Federal Circuit's “cryptic mandate.” Enzo argued that the district court should enter judgment in its favor on claims 67, 68 and 70 because the jury already found that the accused products infringed those claims and the finding wasn't affected by the Federal Circuit’s decision concerning claim 1.

Thermo Fisher Scientific countered that the court should enter judgment of non-infringement because the Federal Circuit held that none of the claims-at-issue covers direct detection and there was no dispute that the accused products don't infringe a claim limited to indirect detection.

It also noted that throughout its written opinion the appeals court treated the claims collectively, discussed the language of claim 1 only after labeling it “representative” of the other claims and specifically held that “the district court erred in construing the disputed claims of the patent-in-suit to cover both direct and indirect detection,” again using the plural.

Thermo Fisher Scientific argued as well that the Federal Circuit never addressed the alternative argument that, if the '767 patent covers direct detection, it is invalid for lack of written description or for lack of enablement, indicating that the appeals court wasn't holding that the patent covers direct detection.

Arterton wrote that Thermo Fisher Scientific's interpretation of the Federal Circuit's “ambiguity” was the more plausible of the two. She said, “[T]he Court can conceive of no reason why the Federal Circuit would not have addressed Defendants’ alternative arguments if its holding was not that all of the claims cover solely indirect detection.”

No Infringement by Equivalence

Enzo also contended that summary judgment shouldn't be granted in Thermo Fisher Scientific’s favor as to claims 1 and 8 because indirect and direct detection aren't substantially different so the accused products infringed the '767 patent by equivalence. The court noted, quoting Warner- Jenkinson Co. v. Hilton Davis Chem. Co., 520 U.S. 17, 40 (1997), that, in order to infringe by equivalence, an accused product or process must “contain elements identical or equivalent to each claimed element of the patented invention.”

Thermo Fisher Scientific contended that Enzo's equivalence argument relied on the testimony of its expert witness, which it called “scientific gibberish.” The court again agreed with Thermo Fisher Scientific, stating that because a detectable signal is generated in direct detection and not in indirect detection there is no equivalence.

Other Litigation Not Affected

Accordingly, the court denied Enzo's motion for entry of judgment on the current verdict and granted Thermo Fisher Scientific's motion for summary judgment in its favor.

In its Form 8-K filing, Enzo said the court's ruling doesn't affect other pending litigation. Enzo has an ongoing action against TFS, Hologic, Abbott, Siemens Healthcare, Illumina, Becton Dickinson, Gen-Probe and Roche Molecular in the U.S. District Court for the District of Delaware for infringement of another DNA detection patent .

Enzo and Yale were represented by Hunton & Williams, Washington, New York, Norfolk, Va., and McLean, Va.; Zeldes, Needle & Cooper, Bridgeport, Conn.; and Baker & Botts, Houston. TFS and Tropix were represented by Sidley Austin LLP, Washington; Pullman & Comley, Bridgeport, Conn.; Weil, Gotshal & Manges LLP, New York; and Paul, Weiss, Rifkind, Wharton & Garrison LLP, New York.

To contact the reporter on this story: John T. Aquino in Washington at

To contact the editor responsible for this story: Randy Kubetin at