SAN FRANCISCO — Trouble is brewing for Sequenom as the biotech company tries to revive a prenatal testing patent that U.S. District Judge Susan Illston pronounced dead last fall.

San Diego-based Sequenom Inc. filed a 15-page motion with the U.S. Court of Appeals for the Federal Circuit in January, asking the court to take judicial notice of several scientific facts that it says are uncontested. Sequenom’s opponents fired back Feb. 3, saying the facts are indeed contested and that Sequenom is trying to cover up its failure to develop a full pretrial record.