A Sunni Man and A Shia Woman
Question :

A Sunni man was married to a Shia woman. After some time, they were separated. She filed for divorce against him in the courts. He went to a Sunni judge and divorced her but her civil divorce is not completed yet. Is she considered as divorced? Can she remarry again?

Answer :

If the divorce by the Sunni judge was based on the religious laws of the sect of the husband, the divorce is correct, even if it is not registered in a legal way. She can remarry after observing the waiting period (the iddah).