Blue Origin, Jeff Bezos’ space company, filed a federal lawsuit Friday over NASA awarding a $2.9 billion lunar lander contract to Elon Musk’s rival company SpaceX.

Bezos founded the company to pursue commercial space flight, and after a trip from Texas last month, offered NASA $2 billion to change its mind about the contract. The filing mentioned “NASA’s unlawful and improper evaluation of proposals.”

The federal Government Accountability Office (GAO) stood by NASA regarding its decision to only pick one lunar lander provider. NASA currently must file a response to Blue Origin by Oct. 12, but the current suit remains sealed. 

The GAO said Blue Origin has “denied the protest arguments that NASA acted improperly in making a single award to SpaceX.” Blue Origin has argued that NASA was required to offer more than one award, with there being “fundamental issues” involved.

“We firmly believe that the issues identified in this procurement and its outcomes must be addressed to restore fairness, create competition, and ensure a safe return to the Moon for America,” Blue Origin said in a statement, according to CNN

Blue Origin’s request to keep the court complaint under seal was granted by a judge, as the company claimed it could cause “competitive harm” and could expose “proprietary information, trade secrets, and confidential financial information.”