When SpaceX published its S-1 on May 20, investors got what they expected: a landmark filing for a company planning the largest IPO in history. What they may not have been ready for was the compensation structure buried inside it, which reads less like a corporate pay package and more like science fiction.

The SpaceX board will grant CEO and founder Elon Musk 1 billion restricted shares of Class B common stock on one condition: he has to hit 15 market capitalization milestones up to $7.5 trillion and establish a “permanent human colony on Mars with at least 1 million inhabitants.”

This is on top of his existing stake of roughly 5 billion shares, worth approximately $825 billion now. The new shares, potentially worth several hundred billion dollars more, come with conditions that have no precedent in the history of executive compensation. And the science fiction-ness of the whole condition appears constant throughout the filing.

The word “Mars” appears 63 times in the document, including under the “executive compensation” section. The prospectus is structured, in part, around the argument that getting to Mars isn’t a vanity project but the company’s reason for being. “For the entirety of its existence, human civilization has lived on a single celestial body: Earth,” the filing read. “The current paradigm, in which human civilization is confined to one planet, exposes humanity to existential threats that are unpredictable and uncontrollable on a planetary scale.”