Reference: Fataawa al-Lajnah ad-Daa.imah lil-Buhooth al-‘Ilmiyyah wal-Iftaa. – Volume 13, Page 506, Fatwa No.5524
Question: I had shares in a company that went bankrupt 25 years ago. The representatives of the company bought shares, with the remainder of the money, in Riyad Bank back then (i.e. 25 years ago). Each share was bought for 1,000 Saudi Riyals, and now the value of each share is 30,000 Saudi Riyals. I am need of this sum of money. So, is it permissible for me to take this money as it is [if I sell my share], knowing that the shares in Riyad Bank were bought without our knowledge all this time?
Response: Take all the money (i.e. sell your share), both your initial investment and the profit and keep your initial investment because that is your property. And give in charity [all] the profit. This is because it is ribaa and Allaah will provide for you from His Excellence and will compensate you with better than it, and will aid you in settling your needs. And whoever fears Allaah, then Allaah will make for him an opening and will provide for you from that which you do not know, and whoever puts his trust in Allaah, then that is enough for him.
And with Allaah lies all success and may Allaah send prayers and salutations upon our Prophet ﷺ and his family and his companions.