[Nature of business relationship.

51A. For the purposes of sub-clause (viii) of Explanation below sub-section (2) of section 288, the term "business relationship" shall be construed as any transaction entered into for a commercial purpose, other than,—

(i) commercial transactions which are in the nature of professional services permitted to be rendered by an auditor or audit firm under the Act and the Chartered Accountants Act, 1949 (38 of 1949) and the rules or the regulations made under those Acts;

(ii) commercial transactions which are in the ordinary course of business of the company at arm's length price - like sale of products or services to the auditor, as customer, in the ordinary course of business, by companies engaged in the business of telecommunications, airlines, hospitals, hotels and such other similar businesses.]