§ 15 TDDDG
Calling Line Identification Display and Suppression
(1)Where the provider of a voice communication service offers the display of the calling line identification for incoming calls, calling and called end users must have the possibility of suppressing the calling line identification display permanently or for each individual call in a simple manner and free of charge. Called end users must have the possibility of rejecting incoming calls for which the calling line identification display has been suppressed by the calling end user in a simple manner and free of charge. Where the display of the called end users' calling line identification is offered, called end users must have the possibility of suppressing the display of their calling line identification to the calling end user in a simple manner and free of charge. The display of calling line identification of calling end users must not be excluded for the emergency numbers 112 and 110 and the numbers 124 124 and 116 117.
(2)For calls made for the purpose of advertising, calling users must neither suppress the calling line identification display nor cause it to be suppressed by the provider of the telecommunications service; the calling user must ensure that the calling line identification assigned to the calling user is transmitted to the called party.
(3)Where subscribers so request, providers of voice communication services must provide a connection for which the transmission of the calling line identification is excluded free of charge. Upon application by the subscriber, such connections must be marked in the end-user directory (Section 17). Where a marking under sentence 2 has been made, transmission of the calling line identification of the connection from which the call originates to the marked connection may only take place once the marking is no longer contained in the updated version of the end-user directory.
(4)Where the subscriber has not applied for inclusion in the end-user directory pursuant to Section 17, the display of his or her calling line identification at the called connection shall not take place, unless the subscriber expressly requests the transmission of his or her calling line identification.
(5)Paragraphs 1 to 4 shall also apply to calls to foreign countries and to calls coming from foreign countries, insofar as they concern calling or called parties in Germany.