(1) A firm or permit holder shall not offer or perform professional services for a fee which is contingent upon the findings or results of such services, when the firm or permit holder also performs for that client any services for which professional standards require independence. This prohibition applies during the period in which the firm or permit holder is engaged to perform any services for which professional standards require independence and the period covered by those services.

(2) A firm or permit holder who is not prohibited by this rule from performing professional services for a contingent fee shall disclose that fact in writing to any person or entity to whom the services are to be provided. Written acknowledgment of such disclosure shall be obtained.

(3) A firm or permit holder shall not offer to prepare an original or amended tax return or claim for a tax refund for a contingent fee for any client.