Elon Musk stunned investors on Tuesday by tweeting that he might take Tesla private, using SpaceX, his private space flight company, as a model for how to treat shareholders. If he succeeds, he may set a precedent for other public company CEOs who want the benefits of public ownership without the hindrance of public scrutiny.

It’s not well understood just how much SpaceX has created a new model for corporate ownership. Private tech companies have long struggled with a need to let shareholders sell as easily as public company investors can. SpaceX, a 16-year-old company last valued at about $25 billion, has an unusual approach to that issue.