السَّلَامُ عَلَيْكُمْ
I seek your guidance on a fiqhi question regarding mortgage which I discuss below.
1) A general Ruling
I quote the below Q/A from Sistani.org regarding mortgage from Non-Muslim Banks.
Question: Banks in the West give loans —known as mortgage— to those who do not have enough money to buy houses; this is to be paid back in [weekly or monthly] instalments with a high rate of interest. Is a Muslim allowed to use this facility? If it is not permissible, is there a solution in your view for someone who claims that he needs the mortgage to buy his own residential house and does not possess enough money to pay for it?
Answer: It is permissible to take the money from the bank that is financed by non-Muslim government or private funds but not with the intention of loan. The knowledge that the bank will sooner or later force him to pay the capital as well as the interest does not affect [the lawfulness of] his taking the money.
Source: http://www.sistani.org/english/qa/01239/

2) My Questions
The above ruling provides a way out to get a mortgage from banks “financed by Non-Muslims”.
The question I have is:
“What if the bank is not entirely financed by Non-Muslims and Muslims may hold a minor (e.g. 1%) shareholding in the bank?” Is the above ruling still valid? Would it make a difference if I am certain or in doubt about Muslim ownership/shareholding of these banks?
The reason I am asking this question is that it is almost certain to me that Muslims will have some shareholding in all the big banks which are traded in Stock market. While these banks may originally have been setup by Non-Muslims, Muslims may have later purchased some shares and therefore, will have a minor ownership in the bank.
3) Answers from Ulema
I have also asked this question from ulemas and have received inconsistent replies, one of which I quote below which does not allow taking mortgage in this circumstance:
“If one is certain that muslims have some ownership then the above ruling is not valid in this case. The rationale being that mortgage from Non-Muslims is valid if taken with the intent of securing money (“Istinkas”). In case of mixed (Muslim and Non-Muslim) funds/ownership, the same cannot be applied as one is not allowed to steal/gazb funds from Muslims.”

I will be grateful if you can provide your opinion and guidance on the above matter and advise if taking out a mortgage from such banks is lawful as per Agha Sistani’s fatwas.
Jazakallah Khair
Aun Ali