What is the expiation for one who swore falsely upon the Quran to deny a theft he committed?

The thief must repent to Allah with sincere repentance, and return the stolen money to its owners, even if indirectly. If it is not possible to reach them or their heirs, then he should donate the value of the stolen money as charity on behalf of its owners. If he does not know the exact amount he stole, he must err on the side of caution and take the higher certain amount. He must hasten to repent and seek forgiveness. If he offers an expiation for an oath along with his repentance, that is more cautious.