In an appeal from the USPTO Board of Patent Appeals and Interferences (Board), the U.S. Court of Appeals for the Federal Circuit (05-1119; Interference No. 103,586), in Brown et al. v. Barbacid et al., looked at an invention priority determination (interference” proceeding).

In an interference between Brown and Barbacid over an assay for identifying compounds that inhibit farnesyl transferase (“FT”), an enzyme involved in the control of cell growth, the CAFC reversed Board’s holding that Brown’s reasonable diligence had not been demonstrated. The CAFC held that a laboratory notebook recording daily experimentation does not need to include on every page a statement of the larger research purpose.

The contested subject matter is stated in the interference count was:

A method for identifying a candidate substance having the ability to inhibit a farnesyl transferase enzyme, comprising the steps of:
(a) obtaining an enzyme composition comprising a farnesyl transferase enzyme that is capable of transferring a farnesyl moiety to a farnesyl acceptor substance;
(b) admixing a candidate substance with the enzyme composition and farnesyl pyrophosphate; and
(c) determining the ability of the farnesyl transferase enzyme to transfer a farnesyl moiety to a farnesyl acceptor substrate in the presence of the candidate substance and in the absence of the candidate substance

Earlier, the Board held that Brown had established conception no later than November 15, 1989, but had failed to provide corroborated evidence of diligence and awarded priority to Barbacid.

The party that is first to conceive the invention in interference, if last to reduce the invention to practice, is entitled to the patent based on prior conception if, as first to conceive, he exercised reasonable diligence from a time before the other party’s conception date to his own reduction to practice date.

The purpose of requiring reasonable diligence by the first to conceive the invention but second to reduce to practice is to assure that the invention was not abandoned or unreasonably delayed by the first inventor during the period after the second inventor entered the field. The question of reasonable diligence is one of fact. The admissibility of physical and testimonial evidence is determined in accordance with the Federal Rules of Evidence.

Barbacid argued that Brown must show diligence measured from the Barbacid date of conception, not Barbacid’s date of reduction to practice. Brown provided evidence from inventor Dr. Reiss and laboratory technician Ms. Morgan concerning the exercise of reasonable diligence during the period from Barbacid’s accorded date to Brown’s filing date. Dr. Reiss stated that after September 1989 he worked on the farnesyl transferase project “on a daily basis.” For the period following Barbacid’s actual reduction to practice on March 6, 1990, Dr. Reiss stated that his experiments were directed at further characterizing the FT enzyme, improving the methodology for purifying the enzyme, and improving the overall performance of the assay. He provided laboratory notebook pages recording this work.

The Board rejected Dr. Reiss’ testimony for lack of corroboration, and also observed that even if his notebook records showing this work were deemed to corroborate his testimony, they recorded work on only ten of the thirty-one days from March 6 to April 18, and thus were insufficient to establish reasonable diligence.

Precedent requires that an inventor’s testimony concerning his diligence be corroborated. But, unlike the legal rigor of conception and reduction to practice, diligence and its corroboration may be shown by a variety of activities, as precedent illustrates. The CAFC stated that:

The basic inquiry is whether, on all of the evidence, there was reasonably continuing activity to reduce the invention to practice. There is no rule requiring a specific kind of activity in determining whether the applicant was reasonably diligent in proceeding toward an actual or constructive reduction to practice.

The Board found that Ms. Morgan “worked for the inventors” and that “her work could inure to the benefit of the inventors to establish reasonable diligence over the entire period. “However, the Board refused to credit any of Ms. Morgan’s evidence, criticizing what it described as the absence of explanation of the content and purpose of these experiments.

The CAFC then held that:

We conclude that the Board erred in law, in failing to view the proffered evidence as it would be viewed by persons experienced in the field of the invention. See Mahurkar, 79 F.3d at 1577-78 (the trier of fact is aided by an understanding of how the evidence would be viewed by one skilled in the art). The Board is charged with expertise appropriate to the invention under examination, and with understanding that a laboratory notebook recording daily experimentation, reasonably considered from the viewpoint of persons experienced in the field, need not reproduce on each page a statement of the larger research purpose; this purpose may reasonably be shown in the various declarations.

It is undisputed that the subject matter recorded on the Morgan notebook pages and described in her declaration concerns the subject matter of the count. This is the same form and content of evidence that the court in Brown I deemed admissible for purposes of showing conception. The Board agreed that Ms. Morgan’s activity during the critical period, if accepted into evidence, established diligence. We conclude that the Board erred in refusing to accept this evidence, and that reasonable diligence is deemed established.

The Board’s holding that Brown’s reasonable diligence had not been shown was reversed and the case remanded for a determination on patentability.

See the entire opinion here.

Comments are closed.