بسم الله الرحمن الرحيم
(Fatwa: 5/6/D=01/1436)
If he did not utter talaq or such a word which terminates nikah and did not write any word like this on paper then merely by signing on blank paper talaq did not take place, their nikah is intact. It is lawful for both of them to live like husband and wife together.
Allah knows Best!
Darul Ifta,
Darul Uloom Deoband
