By haram if you mean wealth obtained through bribe, usurping and interest, one is asked to return all these haram wealth to their owners. If the owners are no more alive, he should return the same to the heirs. If there are no heirs or they are untraced after due efforts, he should give such wealth in charity to the poor and needy. But, the halal wealth earned through haram wealth will not be regarded as haram.
Allah (Subhana Wa Ta’ala) knows Best
Darul Uloom Deoband