Directors of company have to sign the form MGT-7 . and if you see the Form MGT-7 it is written there "In case of a listed company or a company having paid up share capital of Ten Crore rupees or more or turnover of Fifty Crore rupees or
more, details of company secretary in whole time practice certifying the annual return in Form MGT-8"
AOC-4 must signed by 1)Director or 2)Manager/CEO/CFO or 3) Company secretary of co. AND a sign by professional 1)CS or 2)CA or 3)CMA. in whole time practice.
ADT-1 shall be signed by 1)Director or 2)Manager/CEO/CFO or 3) Company secretary of co.