Apple is the main customer of many component manufacturers, so it is in a position to force situations that other manufacturers cannot do due to their lower order and workload.
Apple was not very fond of the Zenbook, an Asus-designed laptop that looks suspiciously a lot like the MacBook Air and is made by Pegatron, a company that also makes Mac computers for Apple. Thanks to its privileged position, Apple has asked Pegatron to dissociate itself from Asus on this model and that it does not manufacture it, since they consider that it is a copy of the MacBook Air.
It will be necessary to see if Apple manages to get away with it, and it is that at the moment those of Pegatron remain silent regarding their decision. We will continue to inform about it.
Source | TUAW
I prefer the zenbook 3 to the MacBook air. Just so you know, Asus makes the motherboards for almost all of its Macs. Asus just wants to get to perfection with all of its products and is doing it, Asus is years ahead of Apple.