In In re Construction Equipment Co., 2010-1507 (Fed. Cir. Dec. 8, 2010), the Federal Circuit recently held that even after a patent is litigated to a final decision finding that the patent was valid and infringed, the accused infringer can still initiate, and the PTO can still resolve, an ex parte reexamination of the asserted patent. In 2000, the Federal Circuit affirmed that Powerscreen infringed a valid patent. In 2007, Powerscreen initiated an ex parte reexamination arguing that the patent was invalid. Powerscreen relied on the same references from the litigation, but also introduced new references. The patentee also introduced new claims during the reexamination. The PTO rejected the claims as unpatentable. The Federal Circuit affirmed the decision of the PTO. As an initial matter, the Federal Circuit determined that an accused infringer is not prevented from initiating an ex parte reexamination because of a prior finding in litigation of validity on the same patent. In addition, the Federal Circuit noted that the reexamination involved new references and new claims that were not part of the earlier litigation. Judge Newman dissented, arguing that the PTO finding was barred by res judicata or issue preclusion because of the earlier litigation that upheld the validity of the patent over much of the same art.