All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.
If this person (i.e. the deceased) made his relatives the actual owners of those properties [i.e. they were disposing of those properties as their real owners], then the ownership of those properties was transferred to them and they are entitled to it.
However, if he wrote those properties in their names only on paper as a formality for legal reasons, then it is not sufficient grounds in Islamic law for the transfer of ownership to them; rather, he remains the owner of those properties, and when he dies, those properties are to be transferred to his legitimate heirs – each according to his prescribed share.
Allaah Knows best.