Ref. No. 1346/42-734
In the name of Allah the most Gracious the most Merciful
The answer to your question is as follows:
If the case is so then investing in any of the aforementioned firms is allowed. However, the amount of interest received must be given in charity to the poor without an intention of reward. So, the amount you receive more than you deposited, you have to give it in charity and do not keep a penny of the same with you.
And Allah knows best
Darul Ifta
Darul Uloom Waqf Deoband