A Registered Valuer is an individual registered with the Insolvency and Bankruptcy Board of India (IBBI) under Section 247 of the Companies Act, in a specific asset class — for company shares, that class is Securities or Financial Assets.
Registration requires passing IBBI's valuation examination and membership of a recognised valuer organisation; it is a personal credential that a CA does not automatically hold. The IBBI register is public, so you can (and should) verify any valuer's registration before relying on their report.
Valuations mandated by the Companies Act — preferential allotments, sweat equity, scheme exchange ratios, and more — must be signed by a Registered Valuer. VMS Jhunjhunwala & Co has two Registered Valuers (Securities & Financial Assets) among its partners.