Ofcom is proposing to design the 800MHz and 2.6GHz spectrum auctions to ensure that the UK mobile market remains at four players, through a complex set of rules largely designed to help H3G get the spectrum it needs to remain competitive. However, the sting in the tale is that Ofcom expects H3G to pay around £600m for this spectrum, which it may not want to do, and it is not clear what the backup plan would then be. We expect the general theme of regulators seeking to protect a fourth player to repeat across Europe and across regulatory areas, especially as the US market may consolidate towards three with AT&T’s proposed takeover of T-Mobile USA.