Determining Assignor Estoppel After Hologic Patent Ruling


Publish Date:
September 13, 2022
Related Person(s):
Related Organization(s):


One might think this exception should not apply in a blanket fashion if there was also an inventor oath made at the time the patent application was presented. However, the law review article the Supreme Court cited on this point in Minerva suggests otherwise.

In it, Stanford Law School professor Mark Lemley noted that “[t]he nineteenth-century vision of assignor estoppel was directed at people who themselves sold a patent for profit” because it would be unfair to sell something for value and later “reveal that the thing I sold you was actually worthless.” This rationale does not hold for an employee-inventor who is “required to assign all their inventions as a condition of employment.”

Read More