What is the ruling on signing a contract that includes approval of a man-made law, and is this signature considered among the nullifiers of faith by action?

Any condition that does not make lawful what is unlawful, nor make unlawful what is lawful, is permissible to adhere to and sign, whether stipulated by a Muslim or a disbeliever, and whether these contracts are in the Abode of Islam or the Abode of Disbelief. As for conditions that contradict the Qur’an and Sunnah, it is not permissible to adhere to or sign them. Whoever signs them has committed a sin, but it does not amount to disbelief that expels one from the faith, unless he deems lawful what Allah has forbidden or prefers it over the rulings of the Sacred Law.