Amazon’s iPhone dynamic pricing prior to the Apple keynote

This article implies that it is Amazon that is changing the prices. Many people don't understand this, but Amazon is a marketplace where sellers compete to sell products. There are currently ~120 sellers with offers to sell a new iPhone 5s (space gray) all with different prices and Amazon just picks one to be the default. So this graph is really showing something more akin to a market price for the iPhone 5c.

http://www.amazon.com/gp/offer-listing/B00F3J4B5S/ref=dp_olp...

Is this clearly a result of Amazon's own dynamic pricing or simply third party sellers undercutting each other which is common on close out or soon to be replaced items?

In the case of third party sellers, I don't believe Amazon directly controls the pricing.

Currently, the best price for the iPhone mentioned in the article is offered by a company called "TRUE DIGITAL" and isn't even fulfilled by Amazon.

The Apple store price for the iPhone 5c 16GB for the period in question was US$650. But Amazon sellers were asking and frequently getting, according to the chart, US$670 and seldom less than US$650.

But you could just get on from Apple at the store or with free shipping for US$650. Why would the buyers pay more? Maybe the Amazon sellers making a profit by not paying sales taxes.

I thought that Apple sold iPhones at a wholesale discount to retailers, so shouldn't they be able to make a profit at even lower prices? Competition doesn't appear to have brought prices down to marginal cost here.

Many customers sell their iPhone around the time the new one comes out (using services like iCracked and Gazelle). Basic economics dictates that as supply increases, prices will go down. This is a guess as to what could cause the prices to go decrease so rapidly.

The link seems dead.