It depends on whom you ask as Wall Streeters look for hidden meaning in a letter that AT&T sent to the FCC late last week. The issue at hand is excruciatingly technical: Regulators are considering whether to grant Dish additional time to provide broadband services on some spectrum it wants to buy. Without a waiver, Dish would have to serve 100M people within three years. AT&T urged  regulators to reject Dish’s plea, saying that the public would benefit from the fast build-out while a delay would “confer a substantial windfall on Dish.” What’s interesting is the possible subtext. Credit Suisse’s Stefan Anninger sees the letter as a clear sign that AT&T is salivating over Dish’s spectrum following the collapse of the phone giant’s merger plan with T-Mobile. If the government imposes tough build out requirements on the satellite company then it “could increase Dish’s interest in selling/dealing its spectrum,” he says. He believes that AT&T is interested in “increasing its negotiating leverage when it comes to a potential transaction negotiation with Dish.” But Breen Murray Carret analyst Todd Mitchell says the letter is “a clear indication that an AT&T acquisition of Dish is not in the cards in the immediate future.” The way he sees it, AT&T wouldn’t make such a hostile move if it really wanted to deal with chairman Charlie Ergen, who controls the vast majority of his company’s voting shares. That’s why AT&T’s letter “looks more like a hail-Mary, sour-grapes effort to stop Dish from using the spectrum altogether,” Mitchell says. Dish shares were up 2.8% today while AT&T was up 0.6%.