New York CNN Business  — 

SpaceX’s rivals just blew the cover off the rocket company’s secretive lawsuit against the US government.

Blue Origin, Northrop (NOC) Grumman and United Launch Alliance all received Air Force contracts in October in response to the government’s request for Launch Service Agreement proposals, or LSAs, which are worth hundreds of millions of dollars. SpaceX did not receive an LSA contract. Those awards are at the heart of SpaceX’s new lawsuit, and they want to be involved in the proceedings to protect their interests, according to documents filed Tuesday and Wednesday.

The new filings are the first to disclose what SpaceX is protesting: Elon Musk’s company had sought to keep specific details about its protest secret when it filed the lawsuit last week.

A redacted version of SpaceX’s complaint was also published Wednesday. And the company confirmed in a statement that it “respectfully disagrees with the Air Force’s LSA award decision,” adding that SpaceX is “formally challenging” the awards “to ensure a level playing field for competition.”

Blue Origin declined to comment. ULA, a joint rocket venture between Boeing (BA) and Lockheed Martin (LMT), confirmed it’s intervening and said to direct further questions to the Justice Department, which is representing the Air Force. A spokesman for Northrop Grumman did not immediately reply to a request for comment.

The Air Force developed the LSA to help awardees develop massive new rockets that could one day be capable of launching national security payloads for the military. ULA was promised up to $967 million for its forthcoming Vulcan Centaur rocket. Northrop Grumman, which is building a launch vehicle called OmegA, will receive up to $792 million. And Blue Origin will get $500 million for its New Glenn rocket.

The awards, however, do not guarantee that the new rockets will one day win military launch contracts, which are extremely lucrative and coveted in the space industry.

SpaceX can already compete for military contracts using its existing Falcon rockets. It won the right to do so after filing a lawsuit against the federal government in 2014, ending ULA’s decade-long monopoly on such contract awards.

But SpaceX, like the other companies, is also developing a new launch vehicle: It’s called Starship and Super Heavy, a rocket and spaceship system that Musk has described as the technology that will allow humans to colonize Mars. Theoretically, the rocket could be used to help launch heavy military payloads into orbit as well.

The redacted SpaceX complaint posted Wednesday states that the company’s proposal asked for money to support all three of it’s rockets — the Falcon 9 and Falcon Heavy, which are already operational, and Starship.

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    But officials determined that including Starship would render “the entire SpaceX portfolio the ‘highest risk’” of all the options. SpaceX called that claim “unreasonable,” according to the complaint.

    “The Agency wrongly awarded LSAs to a portfolio of three unproven rockets based on unstated metrics, unequal treatment under the procurement criteria, and opaque industrial planning,” SpaceX alleged.

    Musk met with Department of Defense officials in December, according to a recent government report, and at the time he lamented that SpaceX had “written a poor proposal” for the LSA contract and “‘missed the mark.’”

    SpaceX says it determined the contract awards were flawed after reviewing the decision more closely.