Nilssen v. Osram Sylvania, Inc., __ F. Supp.2d __, 2006 WL 1891807, (N.D. Ill. July 5, 2006) (Darrah, J.).

After a six-day inequitable conduct bench trial, Judge Darrah held each of the eleven patents-in-suit unenforceable based upon the pro se plaintiff/inventor’s inequitable conduct before the Patent & Trademark Office (“PTO”). Plaintiff’s inequitable conduct included: submitting misleading affidavits to the PTO; improperly claiming small entity status; falsely claiming priority dates to avoid prior art; failing to disclose related litigation during prosecution; and failing to disclose material prior art to the PTO during prosecution. The Court, however, refused to hold that all patents related to the patents-in-suit were unenforceable under the unclean hands doctrine.

This opinion provides a detailed primer on the many types of misconduct that an applicant may commit before the PTO.  It also serves as a cautionary tale for inventors considering prosecuting patent applications pro se.