Professional DJ trying to justify his fee on the basis of ProDub?
Does your DJ play music that is stored digitally, for example mp3 files played through a laptop? If so, he could very well fall under the remit of the ProDub licence. This allows the holder to convert a limited number of songs from one format to another - for example, from CD to mp3 file - or to keep multiple copies of digital songs.
The only legal way for a DJ to play mp3-type files is if he plays back the exact same copy of the file that he downloaded from a legitimate source such as iTunes or Amazon, from the very same device that he downloaded it onto.
If your DJ tells you that's exactly what he does, then he mustn't have any backup in case his computer crashes during the performance - and as well all know, computers are prone to crashing! "Backup" could mean alternative playout devices or additional hard drives/memory sticks.
So, in short, if yours is a 'Digital DJ' and doesn't have a ProDub, then the only legal way he can play his music is if it is legitimately sourced AND is played from the same device it was downloaded onto in the first place AND has not been modified in any way or duplicated.
What IS ProDub?
ProDub is issued by the PRS for Music (aka "The Performing Rights Society") to protect copyright in recorded works, and to ensure fair distribution of royalties to their artists.
Venues with PRS licences which allow various forms of musical entertainment on the premises - from radios and jukeboxes through to live bands and discos - have a duty to ensure that digital music played at the venue is properly governed in line with the ProDub terms and conditions. Otherwise they are in contravention of their own licence terms which could result in their licence being rescinded or not renewed.
If your venue determines that your DJ needs ProDub, and your DJ cannot prove he has Produb, he will most likely be refused access.
Mobile Disco Myths
Run your own mobile disco company?
Despair at the onslaught of Sids in your area?