So, according to this article, Apple was making a deal with Sun to use ZFS, and later finally dropped it after an alleged discussion between Steve Jobs and Larry Ellison when Oracle owned it.

My question is why did Apple think they needed to make a deal to use ZFS in the first place, and if so has Canonical (who says they'll ship openZFS with Ubuntu) made a deal with Oracle ?

It's true that OpenZFS is more than Oracle's ZFS, but unless I'm mistaken, the vast majority of code in that project is still owned by Oracle.

This article makes me uneasy.