(2) The certificate given under sub-rule (1) shall be valid for the assessment year specified in that certificate, unless it is cancelled by the Assessing Officer at any time before the expiry of the specified period.
(3) An application for a fresh certificate may be made, if required, after the expiry of the period of validity of the earlier certificate given under sub-rule (1).
(4) The certificate shall be valid only for the person named therein.
(5) The certificate shall be issued direct to the person responsible for collecting the tax under advice to the buyer who made an application for issue of such certificate."
Reference/Source: Check at Income Tax site for latest version of the Rules - link