In reply to Alexandre Simard.

He personally do not, but some of it might be done as a work for automattic which will mean that as the CEO he does hold the copyrights. Anyway, even if he don't hold the copyright the only difference that it will make is that he can not personally sue them, and I assume that no one wants to go to court and start arguing about if the use of that code is a violation but still legal because it falls under "fair use" part of the copyright law.