The BBC, reports that the Office of Fair Trading (click here for info) is to look into whether LiveNation's merger with Ticketmaster is legal or if it unfairly hampers their competition and disadvantages customers.
The US authorities have recently launched an investigation themselves.
The joint company officially provided tickets for the Download Festival and between them pretty much every medium-to-massive metal/rock band's tours over the last coupe of years including In Flames, Judas Priest, Trivium, Opeth, Gallows, Motorhead, Iron Maiden, Bullet for My Valentine and a gazillion others. Perhaps that's a reason why they could be getting into hot water...
They also sell tickets for all other kinds of music too, obviously.