Jeff Bezos’s Blue Origin is challenging a U.S. government contract with Elon Musk’s SpaceX to develop technology to land people on the moon again.

In a complaint filed Friday in the Court of Federal Claims in Washington, Blue Origin said the National Aeronautics and Space Administration’s evaluation process was “unlawful and improper.” The complaint was filed under seal but tandem documents seeking a protective order gave an indication of its contents.

NASA selected SpaceX’s human lander bid on April 16 leading Blue Origin and a bidding partner, Dynetics Inc., to file protests with the Government Accountability Office less than two weeks later alleging that the award process was flawed. The GAO denied that protest on July 30 saying that NASA’s SpaceX selection had been made properly. Blue Origin, which has offered to contribute more than $2 billion of work on the project at no cost to the government, had vowed to continue pursuing the matter.

After a much-anticipated GAO denial of Blue Origin and Dynetics protests over NASA’s decision to solely award SpaceX a contract to turn Starship into a crewed Moon lander, an in-depth (but heavily redacted) document explaining that decision was released on August 10th.

Aside from ruthlessly tearing both companies’ protests limb from limb, the US Government Accountability Office’s decision also offered a surprising amount of insight into SpaceX’s HLS Starship proposal. One of those details in particular seemed to strike an irrational nerve in the online spaceflight community. Specifically, in its decision, GAO happened to reveal that SpaceX had proposed a mission profile that would require as many as 16 launches to fully fuel a Starship Lander and stage the spacecraft in an unusual lunar orbit.

After around 24 hours of chaos, confusion, and misplaced panic, SpaceX CEO Elon Musk finally weighed in on the GAO document’s moderately surprising indication that each Starship Moon landing would require sixteen SpaceX launches.