Share data from derivative database

Hi evreyone, I have a question on share data... the fact that if I used OSM data of POIs I have to credit OSM for the data that I will use (and this was never under discussion), than if I use for example phone numbers of POIs from OSM data and than add my onw data when OSM data will be missing, I'm doing a derivative database and for this reason I have to share the data. The question at this point is...how? I mean, I have to share only if someone asks me? Or I have to add by hand all the new data as a normal user or I have to send the database to someone? Thanks in advance