StemCells to begin patent reexamination process

In June, StemCells said that the four patents were pending reexamination by the US Patent and Trademark Office (PTO) based on petitions from Neuralstem. StemCells also noted defendants often petition for reexamination as a tactic to delay litigation and that patents can be reexamined based upon any prior art not previously considered, regardless of whether the prior art is ultimately found to be relevant.

The company added that the PTO often initially rejects reexamined patents, but then subsequently upholds patent claims in later stages of the review and appeals process. StemCells noted that only one of the more than one hundred and thirty claims in the four patents needs to survive in order for the litigation to continue.

Martin McGlynn, president and CEO, said: “We fully expected the PTO's preliminary decision. In a patent reexamination, the patent office will routinely reject all claims under reexamination in order to shift the responsibility of proof back to the patent holder. We remain confident that we will be able to reaffirm the novelty of these inventions and that broad claims protecting the manufacture and use of neural stem cells will emerge from this process. At that time, we will press forward with our case against Neuralstem.”