Change of name of private limited company

As of now, there is no legal requirement as such for specifying old  name.  It is just for sake of easy identification that you can mention old name also on letter heads, invoices, advertisements, notice boards & other documents etc. for some period (say one year or so).

This provision is mentioned in section 12 of the Companies Act, 2013. But section 12 is not yet notified. So as of now no such requirement.