Paying Zakah on behalf of some person without asking his permission

Q: Allah willed that I worked in investing another person's money. After the passage of the full Hawl (one lunar year calculated from the time a property reaches the minimum amount upon which Zakah is due), he did no permit me to pay Zakah (obligatory charity) due on the sum. However, I paid it. Does this payment of Zakah for my reward of for his? (Part No. 8; Page No. 339

A: Your payment of the Zakah due on the wealth of your partner without his permission does not free him from the obligation and he should pay the due Zakah or deputize you to pay it. You should pay him back what you have spent of his money as Zakah without his permission, unless he consents your act and takes nothing from you.May Allah grant us success. May Allah's Peace and Blessings be upon Prophet Muhammad, upon his family and his Companions!