Dyax Corp Prevails at PTAB by Proving 11 Months of Diligence

The Patent Trial and Appeal Board (PTAB) recently handed biopharmaceutical company Dyax Corp. (Dyax) a win in Interference No. 105,809, ruling that Dyax successfully demonstrated that an allegedly anticipatory patent reference was not available as prior art against Dyax’s patent application.

During the interference, Dyax offered proof that its inventors had conceived the claimed invention before the October 31, 2000 filing date of the patent reference and exercised reasonable diligence from before that date through the October 1, 2001 filing date of Dyax’s earliest priority application, resulting in 11 months of diligence.

Such successful long diligence showings are very rare. Gaps of only a few days can preclude a finding of diligence, especially in an inter partes proceeding such as this where the opponent has an opportunity to cross-examine witnesses and submit opposing arguments and evidence. Dyax’s evidence proving prior conception was assembled from a careful review of laboratory notebooks and other documents over a decade old, as well as testimony of prior patent counsel, European inventors, and scientists who had long-since left the company. The PTAB found “that the extensive documentation provided by Dyax . . . sufficiently demonstrated continuous diligence” for the 11-month period.

In a prior decision, the PTAB denied several motions against Dyax and granted Dyax’s motion that Adimab’s patented claims were unpatentable over the patent reference Dyax successfully antedated. Accordingly, the PTAB also entered judgment against Adimab, cancelling all the claims of Adimab’s involved patent.

Dyax was represented by Michael T. Siekman, Lawrence M. Green, Y. Jenny Chen, and Chelsea A. Loughran of Wolf Greenfield.

Adimab was represented by Brenda Herschbach Jarrell, Eric J. Marandett, Fangli Chen, and Justin P. Huddleston, Choate, Hall & Stewart.