That actually does, quite nicely, compromise "Prior Art" that invalidates both the primary claim (claim 1) and the secondary claim (claim 16) — all other claims rely, either directly or indirectly, on those two.

In other words, this single piece of "prior art" — if it is validated during a re-examination of this patent — will cause the patent to disappear entirely.

As far as I can tell this patent fails the Bilski test. It is neither tied to a particular apparatus or machine, nor does perform a unique transformation.

IANAL, but the test outlined in Bilski seems to make this patent NULL. Anyone can implement a one-click system on any machine connected to the internet.

The obviousness test is also valid in this case - at the time Amazon was pushing this through the USPTO... Well, my boss was handing me work from different clients that wanted a sign-in and one-click ordering system for their commerce sites. I had to tell him it was legally impossible each time.

So failing the "obviousness" test - it was a clearly obvious step to take. To both the people writing the code for commerce sites and to the people paying to have them written... And also seeming, to me (and I repeat - IANAL), failing the tests outlined in the Bilski case... Amazon can fight as much as they want, but this patent is a dud.