Their work returned

This is true in many places: if someone comes into your shop and wants their work returned they can’t do so without paying first; if you want to create some artwork or make some sound effects you need a license from someone who owns the rights; if someone wants to give you money for your services (and hence needs your permission) they will need to pay a fee before doing so; if someone hears something in public that sounds like it was recorded by them (which is often how we record public events) they can sue us. 

Make sure not only that your company has good legal counsel but also has legal counsel who understand how these things work and are prepared for them. Also make sure that when people come into your office with their own equipment there is someone either on site or nearby ready with a laptop who can turn everything off (if not already done).

 

With such a long history of government offices being used for other purposes than recording audio, many governments have created rules about what types of devices may be brought into them and whether these devices may be turned off (or even allowed on) during recording .