I’d referred to Hal Wegner’s note on chemical obviousness in the last post. For those interested, the Patent Prospector provides an excellent summary of this note and also links to the note. The summary is as below:

Hal Wegner has analyzed the current status of case law regarding chemical compound obviousness, and holds that “KSR and Pfizer v. Apotex manifest fundamental misunderstandings of chemical practice case law.”

Selective excerpts from the summary of this exceptional research and analysis:
The law of obviousness of a chemical compound evolved from late nineteenth century structural obviousness case law that became highly defined in the 1940’s and was modified in the early 1960’s to provide a balanced two part analysis: The Examiner has the initial burden to establish prima facie or “structural” obviousness, but where this is established, it is up to the patent applicant to present rebuttal evidence demonstrating actual differences between the claimed compound and the prior art.

Over a period of decades, literally thousands of cases, largely at the Board of the U.S. Patent and Trademark Office (PTO), have established an intricate doctrine of “structural” obviousness. An equally intricate body of CCPA case law starting in the early 1960’s created a framework for demonstrating the nonobviousness of the invention as a whole by proving actual differences in properties over the prior art. Shortly after Papesch, the court focused upon whether a compound which is “obvious to try” – and hence prima facie obvious – could nevertheless be demonstrated to be as nonobvious as a whole through a Papesch-based showing of unexpected differences.

Predating the Supreme Court consideration of obviousness in the mid- 1960’s, the CCPA case law on chemical practice was completely consistent with the later evolution of the Supreme Court precedent in that decade. Consistent with Supreme Court precedent, a central and primary focus of the chemical compound obviousness inquiry is upon the differences in properties of the claimed compound versus the prior art compound.

Because the case law at the Supreme Court has focused upon combination patents, there is an assumption made in some quarters that virtually all patents are to combinations. In fact, there has never been a modern Supreme Court grant of certiorari to consider the chemical obviousness case law line relating to a new compound nor any case in modern times to consider the obviousness of any invention other than a combination patent.

The KSR opinion contains loose language concerning whether an invention is “obvious to try” which places this arcane maxim center stage, grist for litigation and appellate resolution at the Federal Circuit.

Pfizer v. Apotex Repudiates Papesch – More than forty years after the establishment of the current case law regime and after nearly twenty-five full years of judicial acceptance – throughout the history of the Federal Circuit – CCPA case law on chemical obviousness is under direct attack in a panel opinion. With the support of one additional member of the panel, the Chief Judge of the Federal Circuit has issued what is undoubtedly the single most controversial chemical practice ruling in the history of the Federal Circuit.

It is easy to criticize mistakes in judicial opinions, but here a major share of the blame for the problems in both KSR and Pfizer v. Apotex is due to inadequacies of legal scholarship in the briefing process.

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