Throughout the past few years no one knew exactly what the agreement was between Apple and AT&T regarding the iPhone. Yes, we all know that they had an exclusive deal, and that Apple was probably getting a huge paycheck from AT&T. But how long is this contract valid?

Today a report surfaced on Engadget.com saying that Apple and AT&T agreed in 2007 to a five-year exclusivity deal for the iPhone, based on filed court documents in California.

Here’s the deal: an ongoing California class-action lawsuit filed in 2007 claims that Apple and AT&T illegally exerted a monopoly over iPhone service by telling customers the iPhone’s required service contract was two years long when the Apple / AT&T exclusivity deal was actually for five years — thus requiring buyers to re-up with AT&T for three years (and not, say, T-Mobile) if they wanted to keep using the iPhone. Obviously Apple had to respond to these allegations, and in addition to arguing that no one was ever promised an unlocked iPhone after two years, the company’s lawyers repeatedly confirm the existence of the five-year agreement while noting it was publicly reported in¬†USA Today.

Assuming that this 5-year deal is still in effect, we’re going to have to wait ’till at least next year to be able to use a different carrier. However, there have been suggestions that Apple and AT&T may agree to extend their exclusivity deal. In my opinion, in order for Apple to agree to this AT&T is going to need to lay down a nice big check.¬†Otherwise, I think complaints from customers about AT&T will likely sway Apple to open their doors to other carriers.

I guess we’ll wait and see!