When it comes to Apple dealing with carriers to allow them to officially carry the iPhone on their networks, the deals they make are pretty much a secret, although it has been suggested in the past that usually carriers are required to prepurchase a huge inventory of iPhones and essentially commit themselves to it in order to sell it on their network. In any case it seems that the French government is interested in how Apple conducts their business with carriers, at least in France, and have launched an investigation and are looking into the contracts Apple and the French carriers have signed with one another.
At this time both Apple and the French government’s anti-fraud and antitrust unit has yet to comment on the matter. It is unclear why the French government is suddenly so interested in how Apple conducts its business, but presumably they might be worried about unfair competition. In fact prior to NTT DOCOMO officially signing on with Apple to offer the iPhone, the Japanese carrier did state in the past that one of the reasons they were hesitant to sign with Apple was due to the numerous obligations that they would be held to if they were to sign the deal, so perhaps this could be something the French government is curious about.