“Business Auxiliary Service” means any service in relation to, — (i) promotion or marketing or sale of goods produced or provided by or belonging to the client; or
(ii) promotion or marketing of service provided by the client; or
[Explanation – For the removal of doubts, it is hereby declared that for the purposes of this sub-clause, “service in relation to promotion or marketing of service provided by the client” includes any service provided in relation to promotion or marketing of games of change, organised, conducted or promoted by the client, in whatever form or by whatever name called, whether or not conducted online, including lottery, lotto, bingo;]
(iii) any customer care service provided on behalf of the client; or
(iv) procurement of goods or services, which are inputs for the client; or
[Explanation — For the removal of doubts, it is hereby declared that for the purposes of this sub-clause, “inputs” means all goods or services intended for use by the client;]
(v) production or processing of goods for, or on behalf of the client; or
(vi) provision of service on behalf of the client; or
(vii) a service incidental or auxiliary to any activity specified in sub-clauses (i) to (vi), such as billing, issue or collection or recovery of cheques, payments, maintenance of accounts and remittance, inventory management, evaluation or development of prospective customer or vendor, public relation services, management or supervision, and includes services as a commission agent, but does not include any activity that amounts to “manufacture” of excisable goods.
more details http://www.servicetax.gov.in/st-profiles/business-auxi.htm