TULSA, Okla., Feb. 8, 2013 (GLOBE NEWSWIRE) -- On February 7, 2013, Syntroleum Corporation (Nasdaq:SYNM) filed suit against Neste Oil Singapore Pte Ltd with the High Court of Singapore asserting its Singapore Patent No. 172,045 entitled "Even Carbon Number Paraffin Composition And Method of Manufacturing Same." In the court filing, Syntroleum alleges that Neste's "operation at its renewable diesel refinery in Singapore involves the processing of a bio-renewable feedstock to produce a hydrocarbon composition having at least 75 wt % even carbon number paraffins" which Syntroleum alleges "is claimed at the very least, in claim 22 of the Patent." Syntroleum's patent issued on November 15, 2012, and expires on December 10, 2028. Syntroleum's action against Neste is not the first dispute between the parties. In May 2012, Neste Oil Oyj sued Syntroleum for alleged infringement of Neste's U.S. Patent No. 8,187,344. On January 31, 2013, the United States District Court for the District of Delaware granted Syntroleum's motion to stay Neste's lawsuit pending reexamination of the '344 patent by the U.S. Patent & Trademark Office (USPTO). Previously, the USPTO had granted Syntroleum's inter partes reexamination request and issued a September 14, 2012 Office Action initially rejecting all claims of the '344 patent as obvious in view of the prior art. The '344 patent is related to and shares the same inventors as a prior Neste patent (U.S. Patent No. 7,279,018), and both are directed to a fuel composition for diesel engines. The USPTO's recent Order is consistent with a prior finding on March 22, 2012 by the USPTO's Board of Patent Appeals and Interferences affirming the Examiner's rejection of the '018 patent's claims. Neste declined to appeal that ruling and on July 31, 2012, the USPTO issued a Reexamination Certificate canceling all claims of the '018 patent. The reexamination proceedings involving the '344 patent remain pending. Syntroleum continues to defend a second suit filed by Neste on December 20, 2012 in the District of Delaware alleging patent infringement of U.S. Patent No. 8,212,094. The '094 patent covers similar subject matter and shares a common inventor with Neste's '018 and '344 patents. Syntroleum denies Neste's claims and will continue to vigorously defend against the Neste patents and is confident that its position will be vindicated.