What is the ruling on trading shares of companies that do not have tangible assets after they are listed on the stock exchange?

Selling company shares before they have tangible assets and while they are still in cash is considered a type of currency exchange (sarf) and its rules apply. For the share trading to be valid, the cash or debts alone, or both combined, must not represent the majority of the project's net assets. In Mudarabah (partnership) sukuk, if the Mudarabah capital is in cash before work commences, then trading it is considered an exchange of cash for cash, and the rules of sarf apply. If it becomes debts, the rules for trading debts apply. If it becomes mixed assets of cash, debts, tangible goods, and usufructs, then trading at a mutually agreed price is permissible, provided that tangible goods and usufructs constitute the majority.