Is it permissible to borrow against prohibited investment certificates—with the bank bearing the return—in order to avoid losing a quarter of the capital upon their cancellation, and in an effort to utilize the remaining amount for charity?

If canceling usurious certificates would lead to a loss of a quarter of the capital, then it is not forbidden to leave them until their term, with the intention of getting rid of their usurious interest by spending it on charitable causes, to avert harm from the owner of the money. This is also because the one who repents from Riba has the right to reclaim their full capital, as affirmed by the Almighty’s saying: "And if you repent, you may have your principal sums. Wrong not, and you shall not be wronged." Furthermore, the bank's benefit from discounting the amount upon breaking the deposit might exceed the benefit of it remaining until the end of its term, and the rule is to choose the lesser of two harms. However, borrowing with these certificates as collateral is not permissible, as it involves committing Riba once again.