I'd assume they meant OBD3
http://straighttalkautomotive.com/articles/have-you-heard-of...
It's mostly about surfacing the codes via a screen in the car instead of having a generic check engine light and needing an external scanner.
As far as I can tell, it was never mandated. Most posts about it are from ~2011.
> I googled for this and could find no info. Please give a reference for this claim.
I can't even seem to find any reference to odb 3 existing at all in the first place. So yeah any link would be very much appreciated