Please Help: Gratuity

Please advise , the case is below :-

1 Company have 5 brand and subsequent they make 5 company after 6 year , 5 other company opened and transfer all assets , Liabilities and employees to their respective company in which brand gone

After 6 year , 1 employee left the orgainsation so total working of that employee is = 6+6 = 12 Year

What is the status of gratuity payment in this case , can employee get 12 year gratuity from current employer

Please suggest with case law