Last month, it approved the Jordan Cove LNG Project and Pipeline.
Oregon state agencies are arguing that FERC improperly issued a conditional approval for the project.
They say it issued the approval despite multiple failures by the Canadian company behind the project, Pembina, to acquire necessary state permits.
State law requires anyone removing or filling certain amounts of material in Oregon waters obtain a permit.
The Jordan Cove Project and accompanying pipeline would extend from Malin to Coos Bay where gas would then be liquefied at Jordan Cove to be exported.