A possible SpaceX stock market debut is good news for its workers, who stand to turn their company shares into life-changing money.

• A SpaceX IPO would hand big payouts to current and former employees who were paid partly in company stock.
• Around 4,400 workers could become millionaires, and about 400 could make $100 million or more.
• This reaches beyond engineers — even hourly workers at launch sites and Texas facilities hold shares.
• Elon Musk would gain the most, likely becoming the world's first trillionaire.

Outlook: If the IPO goes ahead, thousands of SpaceX staff suddenly get rich, though no firm date has been set.