AT&T's proposed acquisition of T-Mobile was a big deal as soon as it was announced, but now Reuters has unearthed some more context to lend it even more cruciality. We already knew that in the event of AT&T&T-Mobile failing to garner regulatory approval, AT&T would owe Deutsche Telekom, the current owner of T-Mo USA, $3 billion in cash, some spare AWS spectrum, and a roaming agreement "on terms favorable to both parties." Reuters' sleuths say that the spectrum in question is worth $2 billion and the roaming deal a further $1 billion, bringing the total breakup payout to a hair-raising $6 billion. Given the wording of the two companies' deal, we don't expect the roaming part of that settlement would be free for T-Mobile (so $6b looks to be a bit of an over-estimation), but the fact remains that AT&T is staking a whole lot of moolah on this takeover going through. Whether it does or not, Deutsche Telekom's René Obermann (above left) looks assured to still be laughing this time next year -- but will the same be true of AT&T's Randall Stephenson?