§ 10 TDDDG
Charge Calculation and Billing
(1)The processing of traffic data under Section 9(1) sentence 1 by persons obliged under Section 3(2) sentence 1 Nos. 1 and 2 for the purpose of calculating charges and billing end users may only take place in accordance with paragraphs 2 to 4. Where a provider of a telecommunications service provides its services via a public telecommunications network of another operator, that operator may transmit to the provider of the telecommunications service the traffic data collected for the provision of its services. Where the provider of a telecommunications service has concluded a contract with a third party for the collection of charges, the provider may only transmit traffic data under Section 9(1) sentence 1 Nos. 1 to 3 and 5 to the third party insofar as this is necessary for the collection of the charges and the preparation of a detailed invoice. The third party may only process the data for this purpose. The third party must be contractually obliged to maintain the secrecy of telecommunications and to observe the data protection obligations incumbent upon the provider of the telecommunications service.
(2)Persons obliged under Section 3(2) sentence 1 Nos. 1 and 2 must, after the connection has ended, determine without delay from the traffic data under Section 9(1) sentence 1 Nos. 1 to 3 and 5 the data necessary for the calculation of charges. These data may be stored for up to six months after the invoice has been dispatched. Data not necessary for billing must be deleted without delay. Where the end user has raised objections to the amount of the connection charges invoiced before the expiry of the period under sentence 2, the data may be stored until the objections have been conclusively resolved.
(3)Insofar as this is necessary for billing between the provider of a telecommunications service and other providers of telecommunications services or their end users, and for billing between other providers and their end users, the provider and participating persons under Section 3(2) sentence 1 Nos. 1 and 2 may process the traffic data under Section 9(1) sentence 1 Nos. 1 to 3 and 5 necessary for the calculation of charges.
(4)Where the provider and participating persons under Section 3(2) sentence 1 Nos. 1 and 2 collect with the invoice charges for services of a third party that were provided in connection with the provision of telecommunications services, traffic data under Section 9(1) sentence 1 Nos. 1 to 3 and 5 may be transmitted to the third party insofar as this is necessary in the individual case for the enforcement of the third party's claims against its end user.