Diagrams posted over on NeoGAF show that at one time, Wii U’s controller had analogue sticks instead of the Circle Pad sliders similar to those of 3DS.
Through the link, you can see comparison shots of the how it used to look and how it looked when the firm showed it at E3.
The shots posted don’t link to any specific USPTO documents, but they look similar to ones we have seen before.
Documents dug up last week, and filed in September 2011, show Nintendo was considering a voice recognition system as well as HD and glasses-free 3D into its tablet-like controller.
Nintendo has said it plans to show Wii U again at E3 in all it’s finished glory. The console is expected sometime this holiday season.