Regarding the zakat on the profits of sharikat al-mudarabah (profit-sharing partnership), is the zakat considered similar to other expenses, such that the profits are distributed only after the zakat has been deducted, or is each partner responsible for paying the zakat on his earned profits?
Each one of the partners must pay the zakat on his share of the profits. After the expenses are deducted―and the zakat is not considered part of the expenses that are deducted prior to the distribution of profits―the rabb al-mal (capital provider) takes his capital and his profits and pays the zakat on all that, and the mudarib (entrepreneur) collects his share of the profits and pays the zakat on it.
Of course, each of them must combine the aforementioned amounts with the rest of his wealth on which zakat is due [and then pay zakat on the total].
Kuwait Finance House