To automatically check if digital elements such as advertisements, images, voices, pictures, tests, etc., are actually broadcast or distributed on digitized media such as digital broadcasts, internets, portable telephones.

The apparatus comprises a receiver 11 capable of receiving at any time digital elements broadcast or distributed with checking data, a checking data holder 12 for previously saving checking data of those digital elements needed to check if having been broadcast or distributed among digital elements to be broadcast or distributed, a judging part 13 for judging whether the checking data of a received digital element is the same as the saved checking data after comparing both data, a checked data holder 14 for saving its checking data plus checked data if the both data are judged to be the same, and an output part 15 for outputting the checked data and the checking data of the received element.