Regulations for Administration on Type II Telecommunications Business Article 23

An Intra-corporation Network Communication Service operator shall reserve its users' essential information at least one year after the contract ends.The users' essential information as referred to in the preceding paragraph shall include name and address of internal units, branch companies, branch institutions, and subordinate companies, the certificate documents of intra-company relation, intra-company numbering proposal, and the circuit number of leased line that connect network between operator and user.If the intra-company relation of a user is subordinate company, an intra-corporation network communication service operator shall submit name and address of a user and the certificate documents of intra-company relation for the Competent Authority records.