How big is the amount involved?
If HR is proactive documents of employees will be verified from time to time and updated with latet changes and employees should be adviced on importance of proper nomination,latest verified addresses etc.
Please do formalities as Mr Nath Rao has suggested as you need to handle practically things manageable.As there is lapse on your company part as well.Such as no address etc.When there is no nomination declared by deceased employee in documents,it is succession certificate that is only thing making clear about legal status of claimant(s) in dues to be paid.
Labour Law Adviser
It is legally safe to ask claimant to produce succession certificate from competent court.
This will keep company clear from any issue or subsequent claimant.
Putting ad in news aper etc is ok,but we as HR need to protect company interest first while equally looking after staff.
Upto some amount mere indemnity bon will suffice,but in the circumstances described by original querist,the company sadly enough does not have full details/no details on NOK etc.
So play safe.
It is costly to get succession certificate but there is no suitable option.
HR needs to verify documents from time to time and proactively ask staff to update.
like some one gets married,remind for change of NOK.
Where there is no nominee, or where there is a dispute on who should get the money, the Comoany should approach the authority under gratuity act (Generally the labour commissioner) and ask him to decide who will get the gratuity payment.
You may be required under order of the commissioner to deposit the said amount with him pending his decision.
Details of the procedure is given in the act and rules.