Board Thread:Questions and Answers/@comment-7942847-20130408035442/@comment-4651179-20130413192720

The mini-series where his name was given as "Antonio" (Ultimate Iron Man and its sequel) are no longer in cannon with the Earth-1610, and Marvel even gave them their own reality number.

Further comics set in Earth-1610 have given Stark the name of "Anthony", you can see some examples here.

I hope this helped.