The U.S. Court of Appeals for the Federal Circuit upheld a district court’s finding that based on notebook entries evidencing early appreciation of the claimed inventions by two of the named inventors that five other researchers were improperly named as inventors on a patent. University of Pittsburgh v. Hedrick, Case. No. 2008-1468 (Fed. Cir., July 23, 2009) (Mayer, J.).

The University of Pittsburgh (Pitt) filed suit seeking to remove five inventors from a patent relating to adipose-derived (i.e., fat-derived) stem cells. The patent at issue listed seven inventors. Two prior provisional applications listed four of those seven as inventors. In addition, the improperly named inventors provided information to Pitt to include in the patent application and provided a paper, which was submitted to the Patent Office, showing their research that the adipose-derived stem cells were different from a prior art stem cell.

The Federal Circuit held that the patent resulted from the work of only two Pitt researchers, Katz and Llull, and that the other five inventors should be removed. Lab notebook entries and an article confirmed that Katz and Llull discovered that the mature fat cells could transform into more primitive stem cells and then transform back into mature fat cells. In addition, the inventors had recorded in the lab notebook entries ways to isolate such cells from each other and ways to differentiate the adipose-derived stem cells into muscle, nerve, bone and cartilage cells.

The removed inventors did not challenge the factual findings, but rather argued that Katz’s and Llull’s research was highly speculative and inconclusive until others added their efforts. They further argued that Katz and Llull were required to know that the invention contained every limitation of each claim at the time of conception and further asserted that Katz and Llull did not have such knowledge until other researchers confirmed the claimed properties.

The Federal Circuit found that the removed inventors misunderstood what it means to “know” the limitations of the claims. Knowledge by an inventor “does not mean proof to a scientific certainty that the [inventive] construct is exactly what a scientist believes it is. Conception requires a definite and permanent idea of the operative invention, and necessarily turns on the inventor’s ability to describe his invention. Proof that the invention works to a scientific certainty is reduction to practice.” According to the Court, in the absence of evidence to corroborate the true inventors’ actual knowledge, corroboration can be provided from the knowledge of one of ordinary skill in the art at the time of the alleged conception. Here, the knowledge of one of ordinary skill in the art corroborated obvious properties of stem cells as claimed in the patents. The Court concluded that it was entirely proper for the district court to credit Katz and Llull as having a firm and definite idea that these properties existed in the cells.

Practice Note: This case highlights the importance of implementing effective lab notebook programs and demonstrates how the knowledge of one of ordinary skill in the art can support conception claims.