TULSA, Okla., July 3, 2013 (GLOBE NEWSWIRE) -- On June 26, 2013, the U.S. Patent & Trademark Office ("PTO") issued an Office Action Closing Prosecution and rejecting all claims in the ongoing inter partes reexamination of Neste Oil's U.S. Patent No. 8,187,344. The reexamination was initiated by Syntroleum Corporation (Nasdaq:SYNM) in August of 2012 after Neste filed suit against Syntroleum on May 29, 2012 in federal court in the District of Delaware. On January 31, 2013, the District Court stayed the lawsuit pending the final outcome of the PTO's reexamination of the '344 patent. Mirroring its prior office action (dated September 14, 2012), the PTO has again rejected both the original claims of the '344 patent, as well as the amended and new claims submitted by Neste, as obvious in view of the prior art. The reexamination proceedings remain pending at the PTO under Reexam Control Number 95/002,084. On July 2, 2013, the District Court stayed Neste's second lawsuit in federal court in the District of Delaware (filed on December 20, 2012) alleging infringement of Neste Oil's U.S. Patent No. 8,212,094. The '094 patent covers similar subject matter and shares a common inventor with Neste's '344 patent, but adds nothing new to the field of diesel fuels or methods for making same. On March 8, 2013, Syntroleum filed a petition with the PTO seeking inter partes review of the '094 patent. The District Court's July 2 nd decision was based on the pending request for inter partes review of the '094 patent. Syntroleum expects a decision from the PTO no later than September 2013 on whether to grant the petition for inter partes review, which is currently pending at the PTO under Trial Number IPR2013-00178. Syntroleum denies Neste's infringement claims and will continue to vigorously defend against the Neste patents, and remains confident that its position will be vindicated. Syntroleum has invested substantial time and resources in its proprietary Bio-Synfining® technology and will likewise seek to defend and enforce its intellectual property rights in venues around the world.