Content distributing system and data-communication controlling device

In a content distributing system 1, content includes additional information relating to its use, according to characteristics of the content. A data-communication controlling device 40 generates a judgment table associating additional information and a device ID of a client device to which content having the additional information is permitted to be transmitted, and stores the generated judgment table. Upon receipt of a content request including a device ID from a client device, the data-communication controlling device 40 receives content from the broadcast receiving device 10, and judges whether the content is permitted to be transmitted to the client device, using a judgment table corresponding to additional information included in the received content. When judging that the content is not permitted to be transmitted, the data-communication controlling device 40 prohibits transmission of the content.