If you mean before the IPO, it depends on the stock plan of the company. They may have clauses that prevent trading on secondary markets. I don’t think this is

If you mean before the IPO, it depends on the stock plan of the company. They may have clauses that prevent trading on secondary markets. I don’t think this is fair to employees personally, but it is the norm for companies to have various abusive forms of control over the options they grant employees.