Multiple mandatory fields in form but during different stages of submitting

I have an adobe form that needs to be signed off by the employee, manager, divisional head and HR and should all be mandatory fields. My problem is that I am unable to make these mandatory for each separate person as they use the form and then submit it to the next person. i.e. employee fills out the forms and is required to sign their name and date (mandatory) before submitting this to their manager, when the manager received the form they are required to sign their name and date (mandatory) before submitting this to the divisional head?