The Czech Republic’s two dominant mobile operators are sharing one network and the European Commission thinks this is taking things too far.

When the EC thinks something might be dodgy, but hasn’t totally decided yet, it likes to kick things off by sending a statement of objections to all concerned. This puts them on notice that it’s looking into the situation and initiates an investigation. Hence the network sharing arrangement between the Czech versions of O2 and T-Mobile is now under the EC microscope.

“Operators sharing networks generally benefits consumers in terms of faster roll out, cost savings and coverage in rural areas,” said Commissioner Margrethe Vestager. “However, when there are signs that co-operative agreements may be harmful to consumers, it is our role to investigate these and ensure that markets indeed remain competitive. In the present case, we have concerns that the network sharing agreement between the two major operators in Czechia reduces competition in the more densely populated areas of the country.”

This is an intriguing conundrum; how can something good suddenly become bad when it’s done too much? To be fair, between them T-Mobile and O2 account for almost three quarters of Czech subscribers. If the only other MNO of note – Vodafone – is frozen out of this arrangement that would appear to put it at a massive disadvantage. The EC is also concerned that their collective dominance means they have a disincentive to provide a decent service.