Missing Legal Heir

FOR LEGAL STATUS ONE HAVE TO WAIT FOT 7 YEARS.TILL THAT YOU CAN SIGN A MOU.AND TRANSFER THE RIGHTS ARISING OUT. ALTHOUGH HE APPEARS WITHIN PERIOD OF SEVEN YEARS HE CAN NOT SALE THE PROPERTY AS IT IS ANSCESTRAL ONE.

Get it declared as civil death.  For this you will have to file a suit for declaration in the civil court after following the procedure laid down in sec 80 of CPC.

While I agree with both of my colleagues, I may add that registratin of complaint with police is necessary, which can safe guard your interest in so many other ways in future.  e.g. calculation of period of 7 years, the police will also be in a position to endorse your representaion that the person is missing. 

It is not fair to take any decision in hurry which can be challange in future by the person him self, in case he is found.  No body should be in a position to misunderstand your act of sale of such property in his absent.
 

I agree with Mr.Bhagwat Upadhaya.  A complaint is to filed with the Police for calculation of period of seven years to avoid future complications.