Corrected inventorship doesn’t change patent invalidity finding
The owner of a patent can seek correction of the listed inventors at any time after a patent has issued. But a recent case makes clear that this leniency regarding corrections doesn’t provide the patent owner a second bite at the apple after the Patent Trial and Appeal Board (PTAB) has found the patent invalid.
Case timeline
Implicit LLC owned two patents, both of which originally listed Edward Balassanian and Scott Bradley as the only co-inventors. Both were employees of Implicit’s predecessor company. A third individual, Guy Carpenter, worked with them to implement the invention.
Sonos Inc. sought inter partes review (IPR) of the patents. Under IPR, the PTAB can reconsider and cancel an already-issued patent based on certain types of “prior art” that made the claimed invention obvious or not novel (anticipated) and therefore unpatentable. The board’s final decision is subject to review by the U.S. Court of Appeals for the Federal Circuit.
Sonos cited prior art that had a filing date of December 11, 2001. Implicit claimed that Balassanian and Bradley conceived of the inventions and worked with Carpenter to reduce to practice (that is, actually make and use) the inventions before that date.
The PTAB ruled that all of the challenged patent claims were unpatentable. Specifically, it found the evidence was insufficient to establish the conception of the inventions and communication of the invention to Carpenter.
Multiple rounds of appeals ensued, during which time Implicit obtained certificates of correction under the Patent Act’s Section 256. The corrections added Carpenter as a co-inventor on the patents. The appellate court subsequently directed the PTAB to consider the effect the certificates would have on the board’s earlier decision.
The board concluded that Implicit couldn’t rely on the certificates of correction to change inventorship in the IPR proceedings as a reason to revisit the final written decisions and consider a new argument based on Carpenter being a co-inventor. It found Implicit had forfeited this argument because it didn’t raise the argument before the PTAB until after the final decision. In addition, Implicit waited until after that decision to seek certificates of correction.
Too little, too late
Implicit once again turned to the Federal Circuit for relief. It argued that, because Sec. 256 doesn’t limit the time during which inventorship can be corrected, forfeiture is inapplicable to corrections of inventorship. Sonos countered that forfeiture can apply even after Sec. 256 corrections have been issued.
The appellate court sided with Sonos, noting that diligence generally is required when seeking a correction of inventorship if that correction could directly affect the outcome of a proceeding. That was the case here, the court said. Implicit had the opportunity to correct inventorship and assert the change of inventorship theory earlier in the proceeding — and such a change could have directly affected the trial and outcome.
Although forfeiture can be appropriate in a case where a correction has issued, was it appropriate in these circumstances? The appellate court said it was. Implicit had in its sole possession the evidence of inventorship from the beginning, but it intentionally presented evidence that Balassanian and Bradley were the only inventors. Further, Implicit failed to adequately explain why it couldn’t have made any arguments related to Carpenter in the original proceeding or more diligently sought the inventorship correction.
Time for a change
The Federal Circuit’s ruling makes clear that dragging your feet on inventorship corrections can prove to be costly. The time to make inventorship or priority arguments is when an IPR challenge is first before the PTAB. A simple correction later won’t resurrect an argument that should have been made earlier.
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