I entered into a partnership. I made very clear to the other partners (who actually run the business) that they should not do anything unIslamic no matter how profitable it may be. Now if they do something not allowed, will I be responsible?

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.

If you endeavour to advise your partners and make sure that their transactions are permissible, then we hope that you are not sinful.

Nonetheless, it is better to have a partnership with righteous men with whom one is sure that their money is free from forbidden things and doubtful matters.

If you know that they deal in unlawful transactions, then you are obliged to end your partnership with them, as by being a partner with them, you are helping them in what is forbidden, while Allaah Says (what means): {…but do not help one another in sin and transgression.}[Quran 5:2]

By being a partner with them, you will also be earning forbidden money with them and that has bad consequences in this world and in the Hereafter.

Allaah Knows best.