A copyright managing information processing apparatus includes a storage module for storing copyrighted content including audio data; a first topic module for recognizing audio data in content opened to the public by a to-be-opened information processing apparatus, converting the audio data into text data, extracting keywords from the text data, and conducting topic processing using the keywords to create topic information; a second topic module for recognizing audio data in content stored in the storage means, converting the audio data into text data, extracting keywords from the text data, and conducting topic processing using the keywords to create topic information; and a similarity determining module for comparing the topic information generated by the first topic module with that created by the second topic module for thereby determining presence or absence of similarity therebetween.