What is the ruling on taking a percentage in exchange for informing employees of the names of clients who have contracted with the company without their knowledge, thereby enabling them to obtain their due commission?

It is not permissible for the questioner to take any commission because he is an employee and receives a salary, and he is obligated to fulfill the trust of his work. If the other employees were the ones who brought in the new clients and thus deserved the commission, then the questioner has no right to share in it with them. And if the clients came through other means, then they (the other employees) do not deserve the commission in the first place. So, for whoever deserves the commission, it is not permissible for the questioner to stipulate to them, in order to enable them to take their right, that he shares in it with them, as this is an infringement upon people's rights.