• A flight attendant for SpaceX said Elon Musk asked her to "do more" during a massage, documents show.

• The billionaire founder exposed his penis to her and offered to buy her a horse, according to claims in a declaration.

• After she reported the incident to SpaceX, Musk's company paid her $250,000 as part of a severance agreement.

SpaceX, the aerospace firm founded by Elon Musk, the world's wealthiest man, paid a flight attendant $250,000 to settle a sexual misconduct claim against Musk in 2018, Insider has learned.

The attendant worked as a member of the cabin crew on a contract basis for SpaceX's corporate jet fleet. She accused Musk of exposing his erect penis to her, rubbing her leg without consent, and offering to buy her a horse in exchange for an erotic massage, according to interviews and documents obtained by Insider.

The incident, which took place in 2016, is alleged in a declaration signed by a friend of the attendant and prepared in support of her claim. The details in this story are drawn from the declaration as well as other documents, including email correspondence and other records shared with Insider by the friend.

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According to the declaration, the attendant confided to the friend that after taking the flight attendant job, she was encouraged to get licensed as a masseuse so that she could give Musk massages. It was during one such massage in a private cabin on Musk's Gulfstream G650ER, she told the friend, that Musk propositioned her.

After Insider contacted Musk for comment, he emailed to ask for more time to respond and said there is "a lot more to this story."

"If I were inclined to engage in sexual harassment, this is unlikely to be the first time in my entire 30-year career that it comes to light," he wrote, calling the story a "politically motivated hit piece."

Insider extended the deadline and reiterated the offer to Musk to comment on the claims. He did not respond.