What is the ruling on taking a percentage of the profit from a project in which someone else's money was invested, with the knowledge of the owner of the money and without contributing to the capital?

It is permissible for the agent in a Mudarabah (definition) (Mudarib) to engage another agent with the capital, provided the capital owner explicitly permits it or grants general authorization, such as by saying, "Act according to your judgment." In this case, the profit is divided among the capital owner, the first Mudarib, and the second Mudarib according to their agreement. There is no objection to the first Mudarib agreeing with the second Mudarib on a common share of the profit designated for the first Mudarib.