AT&T Inc. (NYSE: T) may be paying Apple Inc. (Nasdaq: AAPL) a bounty for phones sold in the computer maker's own chain of stores, analysts are reporting. But no one's sure how big the bounty is, and one Unstrung source says it could be as much as $200 apiece for iPhones sold in Apple's retail stores.

Apple was already fielding questions about iPhone revenue on its fiscal third-quarter conference call last Wednesday. "We did not recognize any payments from AT&T related to the June quarter, but we will for the September quarter," Apple CFO Peter Oppenheimer said on the call, refusing to divulge any more details.

Apple did say that it sold 270,000 iPhones in the last 36 hours of the June quarter, will top a million devices by the end of September, and expects to move 10 million of the phones through 2008. (See Apple Preps for Millionth iPhone.)Merrill Lynch & Co. Inc. analysts are suggesting that devices sold by Apple online and via its chain of retail stores could provide an additional "bounty" for the iPod in the form of extra activation payments from AT&T. In a new report, the financial analysts speculate that the carrier formerly known as Cingular could be paying Apple an average activation payment of $200 for each device the computer vendor sells direct.

The analysts write that, assuming 45 percent of the iPhones are sold directly by Apple, the vendor could recive an additional payment of $1.5 billion from AT&T during its financial year 2009. (Apple's financial year starts a quarter ahead of the calendar year.)

Apple shares, already up some 69 percent year-to-date, could see some upward movement if Wall Street figures out just how much Apple is getting from each iPhone sold -- and how much ongoing revenue the computer maker has riding on each phone activated. "While Apple and AT&T have not disclosed details surrounding the revenue share agreement between them, we believe the financial impact to AAPL could be substantial," writes Deutsche Bank AG analyst Chris Whitmore in a note sent to clients Monday.

Unstrung called Apple for comment on the analyst note, but a company spokesperson refered us to the CFO's comments on the earnings call and offered no further information. AT&T hasn't returned calls for comment.

The "bounty" payments are by no means the only revenues that Apple will derive from its new phone. The company will, of course, see hardware sales from the device but also has undisclosed revenue sharing agreements with AT&T for the device that the vendor would not comment on during its earnings call.

Data revenue derived from iPhone usage may also prove useful for AT&T, as downloads of anything from ringtones, MP3s, videos, and games increasingly help to improve the overall average revenue per user (ARPU) figures for many carriers. ARPU is one of the key metrics that Wall Street uses to judge the performance of the major cell providers. The September quarter should provide the first indications of whether the iPhone has yet had any impact on AT&T's ARPU.

The carrier has also managed to gain an incalculable amount of free publicity and marketing from the iPhone launch, which must count as the most reported-on smartphone launch yet seen in the U.S. and likely the world. This was no doubt especially useful to AT&T as it migrated from the Cingular brand.

— Dan Jones, Site Editor, Unstrung