United States: Written Description Requirement Not Satisfied Under Principles of Inherency

In affirming an award of priority by the U.S. Patent and Trademark Board of Appeals and Interferences (the Board), the U.S. Court of Appeals for the Federal Circuit held that a product that is inherently produced by a disclosed process does not satisfy the written description requirement for claims directed to the product when one of skill in the art, reading the application, would not have been aware that the product is produced. Chen v. Bouchard, Case No. 03-1037 (Fed. Cir. Oct. 22, 2003).

The Board declared an interference between U.S. Pat. No. 5,254,580 to Chen, which claimed priority back to July 1, 1992, via a continuation in part, and a pending application of Boucher that had a priority date of December 9, 1992. Chen’s 1992 parent application disclosed a process to produce taxol derivatives and precursors of taxol. The disclosed method did not explicitly state that cyclopropataxols were produced as required by the interference count. Chen argued that cyclopropataxols were inherently described since the process described in examples will "inevitably" result in those compounds. Chen also attempted to establish conception and actual reduction to practice using notebooks that were witnessed by others skilled in the art and a contemporaneous test conducted by a third party for the existence of the product in a compound. The Board rejected Chen’s evidence of conception and actual reduction to practice based on a failure to corroborate the notebooks and on the grounds that the test was not an independent verification of the product because the third party was informed that the product existed in the compound prior to the test. Chen appealed.

The Federal Circuit, noting that compliance with the written description requirement is a factual issue, concluded that there was substantial evidence supporting the Board’s determination, and thus Chen was not entitled to the benefit of his earlier applications. The Federal Circuit noted that there was no explicit description of the claimed product in the 1992 parent application and, as the parent did accurately describe another product (fluorotaxol derivatives) made by the process, there was no error in the disclosure. The Court noted that the 1992 parent application did not describe any physical characteristics of the claimed product and the Federal Circuit also noted that there was no evidence that a person of ordinary skill in the art would have recognized that the product of the count would have been produced from the disclosed process.

The Federal Circuit also held that the Board did not abuse its discretion in failing to consider the inventor notebooks since, even though available, the author of the notebooks did not testify. Thus, the Federal Circuit agreed with the Board that the notebooks were properly excluded under hearsay rules.

However, the Federal Circuit rejected the Board’s exclusion of an independent test for the product conducted by a third party, holding that a tester need not be "kept in the dark" regarding the material being tested in order to corroborate the existence of the material. Holding the error harmless, the Federal Circuit went on to find that Chen had not established that the material tested had all of the limitations of the count and hence, Chen did not meet his burden to establish priority.

Judge Newman dissented on the grounds that the inventor’s own testimony was enough to allow the notebooks to be considered as evidence. Judge Newman noted that the reason that an inventor’s testimony must be corroborated related to the frailties of memories regarding acts relating to conception and reduction to practice, and this concern does not relate to whether notebooks were kept. Judge Newman argued that to require corroboration of everything to which an inventor testifies amounts to a rebuttable presumption of dishonesty simply because he is an inventor.