That seems at odds with TFA itself, which claims "Ford itself recently announced that it was giving up on its goal of developing full self-driving technology, at a cost of $2.7 billion."
Perhaps the standard for "reduction to practice [0]" is a little looser than I'm imagining. I can't even see how this would be covered by sufficiency of disclosure[1] since the apparent non-existence of level 4 or 5 autonomy suggests that no person skilled in the art[2] yet exists.