Obviousness; Scope and Content of the Prior Art; Secondary Considerations

Süd-Chemie v. Multisorb Technologies (Fed. Cir. 2009)

Süd-Chemie holds a patent covering a desiccant container for keeping products dry in shipment. In an infringement action, the Kentucky district court found the patent invalid as obvious. On appeal, the Federal Circuit vacated – holding that the lower court had erred in its analysis of the scope and content of the prior art. There are two primary take-away points from Sud-Chemie. First, obviousness jurisprudence continues to require detailed analysis of the claims and the prior art. I.e., KSR did not suddenly allow handwaving as a substitute for evidence and clear argument. Second, well presented secondary indicia of nonobviousness continue to be important in rebutting obviousness allegations.

Here, the claimed patent required the use of “compatible polymeric materials” used in a laminate seal. The prior art disclosed the use of laminate materials taken from the same general class of materials. However, the Federal Circuit recognized that the prior art did not specify that the selected materials be “compatible” in a way to allow for a proper laminate seal.

This is a case where a definition of the claim term in the specification greatly aided the patentee. The specification defined “compatible” materials as those that “mix on a molecular scale and will crystallize homogeneously.” The prior art reference did not teach this form of compatibility. In fact, the prior art appeared to teach “incompatible” materials.  

Multisorb ignores the fact that while the ’942 patent requires the inner surfaces of the laminate and microporous films to have similar softening points, Komatsu [the prior art] requires the films to have dissimilar softening points. Komatsu thus does not teach the use of a microporous film that is compatible with the inner surface of the laminate film.

Looking at secondary considerations, the Federal Circuit instructed district courts to “attend carefully to any evidence of … secondary considerations of nonobviousness.” Here, the focus is on the surprising and unexpected result that compatible materials formed stronger bonds even without adhesive.

The Federal Circuit did not apply these findings to form a conclusion on the issue of obviousness. Rather, the court remanded for further development of the facts.

[NOTE- This decision is from January 2009]

KSR Extended to Obviate Component Purified from Known Mixture

Aventis Pharma & King Pharma v. Lupin Ltd. (Fed. Cir. 2007).

Altace is the King/Aventis brand of ramipril – a top-selling ACE inhibitor.  The patent claims ramipril formulated “substantially free of other isomers.” The district court found the patent not invalid, but only by a slim margin. On appeal the CAFC reversed – finding the patent invalid as obvious.

Prior Art: One reference (‘944 patent) was filed as a continuation-in-part of an already abandoned patent application. That application was eventually revived, but Aventis argued on appeal that the ‘944 patent should not be awarded the filing date of the parent.  The CAFC found this a potentially interesting argument, but refused to hear the argument because Aventis had failed to make the argument at the district court level.

The appellate panel also agreed that the experimental results of a Shering Doctor constituted 102(g)/103(a) prior art because the Doctor had not abandoned, suppressed, or concealed her prior invention.

Obviousness of a Purified Form: The district court, ruling pre-KSR, found the patent nonobvious. On appeal, the CAFC took a different view – finding that the purified form of a known mixture is prima facie obvious if a PHOSITA would have some reason to believe that the mixture derives properties from particular components.

However, if it is known that some desirable property of a mixture derives in whole or in part from a particular one of its components, or if the prior art would provide a person of ordinary skill in the art with reason to believe that this is so, the purified compound is prima facie obvious over the mixture even without an explicit teaching that the ingredient should be concentrated or purified.

The prima facie case of obviousness is especially difficult to rebut where, as here, the potency of the mixture varies directly with the amount of isomer in the mixture.

The court implicitly distinguished this case from Forest Labs — noting that obviousness may be rebutted by showing difficulty in purifying the mixture.

[A] purified compound is not always prima facie obvious over the mixture; for example, it may not be known that the purified compound is present in or an active ingredient of the mixture, or the state of the art may be such that discovering how to perform the purification is an invention of patentable

Reversed, Patent Invalid as Obvious

Zyprexa Patent Upheld on Appeal

OlanzapineEli Lilly v. Zenith Goldline (Fed. Cir. 2006)

Lilly’s patent covers olanzapine (Zyprexa®) and its use for the treatment of schizophrenia. Three generic manufacturers (Zenith (IVAX), Dr. Reddy’s, and Teva) filed an ANDA and Lilly responded with a complaint in the Southern District of Indiana.  After a bench trial, the district court agreed with Lilly that the patent was valid, infringed, and enforceable.  The defendants appealed to the Court of Appeals of the Federal Circuit.

Anticipation: To anticipate the invention, a prior art reference “must disclose each and every feature of the claimed invention, either explicitly or inherently.”  However, in both Petering and Schaumann, prior art references that disclosed the family of the claimed compound were found to anticipate the claimed compound — even though the claimed compounds were not specifically discussed.

Here, the CAFC found that those cases were not applicable because the closest reference to olanzapine did not spell out “a definite and limited class of compounds that enabled a person of ordinary skill in the art to at once envisage each member in this limited class.”

Obviousness: The CAFC agreed that the prior art references did not suggest a the compound. In addition, Lilly provided strong evidence of secondary considerations, including: “(1) a long-felt and unmet need; (2) failure of others; (3) industry acclaim; and (4) unexpected results.”

The record shows a long-felt need for a safer, less toxic, and more effective clozapine-like drug; a decade (or more) of failure to find a replacement for clozapine; a reasonable amount of commercial success for olanzapine; and a number of awards for olanzapine as indicators of industry acclaim.

Public Use: Prior to filing the patent application, Lilly conducted Phase I clinical safety trials. The court found, however, that the trials were well within the experimental use exception:

In this case, Lilly tailored its tests to their experimental drug safety and efficacy purpose, adequately monitored for results, and maintained confidentiality throughout the duration of the study. The trial court did not err in finding no public use.


In Preliminary Injunction Decision, CAFC Forecasts Post-eBay Jurisprudence

PLAVIXSanofi v. Apotex (Fed. Cir. 2006)

Generic manufacturer Apotex wants to make something similar to Sanofi’s Plavix (clopidogrel bisulfate) and filed an ANDA alleging that Sanofi’s patents were invalid.

The two parties worked together to negotiate a settlement.  The agreement, however, was not accepted by state attorneys general even after new terms were presented. Under provisions of the agreement, the regulatory denial killed the settlement and the parties resumed litigation.

Sanofi then filed a motion for preliminary injunction to stop Apotex from selling its product. Within 21 days, the district court issued a PI. (During that time, Apotex shipped six-months of product). Apotex then appealed the PI.  Preliminary injunction jurisprudence has its own four-factor test that is similar to that of permanent injunctions. The plaintiff must show:

  • Reasonable likelihood of success on the merits of the case;
  • Irreparable harm if an injunction is not issued;
  • Balance of hardships tipped in favor of the plaintiff; and
  • Public interest that is not negatively impacted.

The major difference between the factors for consideration in preliminary injunctive relief and those for permanent relief is that preliminary relief requires a showing of a likelihood of success while permanent relief requires success on the merits as a precondition. Thus, the final three factors will give some indication of how the court will rule in post-eBay injunction cases.

Likelihood of success on the merits: Apotex took the odd position of arguing anticipation based on a broadly worded claim of a prior art patent that was examined during prosecution.  The CAFC confirmed that this made the burden of proving invalidity at trial “especially difficult.”  On obviousness, the CAFC confirmed that the unpredictability of enantiomer activity made the claimed dextrorotatory formation nonobvious even if the molecule as a whole was known.

On Irreparable Harm: The settlement agreement between the parties included a provision that capped any damages for infringement by Apotex — seemingly an admission that Sanofi would settle for money damages. The court did not buy-into this argument, but only because of the technicality that the agreement also contemplated an injunction.

Balance of hardships tip entirely in Sanofi’s favor because Apotex chose to launch its product under threat of injunctive relief.  It could have avoided the situation altogether and thus should not benefit from this factor.

Public Interest: The CAFC continued its line of the “importance of the patent system in encouraging innovation.” Interestingly, the court focuses on how the expense of pharmaceutical inventions necessitates strong patent protection. . . . begging the question of whether less expensive innovations (such as software) have less of a public interest in strong patent protection.