What is the ruling on speculation in the Saudi stock market by buying when prices fall and selling when they rise? And what are the companies, other than usurious banks, whose shares are permissible to buy, knowing that their activity is not among the prohibited activities, but they have usurious loans or impermissible investments?

It is permissible to speculate in stocks, provided that the necessary conditions for the permissibility of speculation and the permissibility of dealing in stocks are met. However, it is not permissible to deal in the shares of companies that engage in usurious loans or impermissible investments, due to the Almighty's saying: "And do not cooperate in sin and aggression."