by , 8:25 AM EDT, July 19th, 2007

Piper Jaffray analyst Gene Munster believes Apple and AT&T have a revenue sharing agreement for the iPhone, and that it will prove to be a plus for Apple's bottom line. He estimates that as part of the deal, AT&T is paying Apple US$3 per month for its customers that change handsets to use an iPhone, and $11 a month for iPhone customers switching from another carrier.

That agreement could prove to be lucrative for Apple since the deal covers the 24 month life of each iPhone user's contract.

"Due to the unique terms of iPhone sales and pricing, we believe AT&T has agreed to a revenue sharing plan with Apple," Mr. Munster said. "And while we do not know the exact details of the agreement, we conservatively estimate that AT&T gives Apple $3 per month (over the life of the 24 month contract) for every iPhone customer already with AT&T and $11 per month for every new subscriber."

While the deal would add only about $0.02 to Apple's EPS for 2007, it could have a much larger impact in 2008 and 2009. He estimates that it could add $0.15 to the company's EPS in 2008, and $0.58 in 2009.

Mr. Munster is maintaining his "Outperform" rating and $160 target price for Apple's stock. Apple is currently trading in the pre-market at $140, up 1.88 (1.36%).