26 Refund of tax 7. If it is proved to the satisfaction of the Commissioner that any person has been charged with tax in excess of the amount properly chargeable in terms of this Schedule, the Commissioner shall authorise a refund in so far as it has been overpaid: Provided that the Commissioner shall not authorise any refund in terms of this paragraph unless the claim therefor is made within three years of the date of payment of such tax. THIRTY-FOURTH SCHEDULE (Section 37B) ADVANCE TAX RULINGS Interpretation 1. In this Schedule— “advance tax ruling” means a written statement in the form of a binding general ruling, binding private ruling or binding class ruling issued by the Commissioner-General regarding the interpretation or application of the Act; “applicant” means a person who applies for a binding private ruling or a binding class ruling; “binding class ruling” means an advance tax ruling issued in response to an application by an applicant regarding the application or interpretation of this Act as it affects a specific class of persons; “binding general ruling” means an advance tax ruling, issued in accordance with the requirements of this Act; “binding private ruling” means an advance tax ruling issued in response to an application by an applicant regarding the application or interpretation of this Act in respect of a proposed transaction as it affects the applicant alone; “class member” means a member of the class to which a binding class ruling applies, such as a shareholder in a company or an employee participant in a share investment scheme; “entity” means a person, other than a natural person, which may apply for a binding class ruling on behalf of its shareholders or members in respect of a proposed transaction to which it is a party and includes a company, private business corporation, cooperative society or trade association: Provided that an entity does not include a professional firm acting or purporting to act on behalf of a client; “nonbinding private opinion” means a written statement issued by the CommissionerGeneral in response to an inquiry by a person in order to provide the person with informal guidance in respect of the tax treatment of a particular set of facts and circumstances or transaction, but which does not have any binding effect;