Sale of non-available goods. This type of contract is not valid in the Islamic commercial law.
Bai‘ al-kali bil kali
Riba al-khafi
Bai‘ al-muzabanah
Fuduli
Rabb al-mal
Bai‘ al-munabadhah
Dain marju al-ada
Mute Investment
Business Angels
Riba al-nasi'ah