  A tree-based network $N$ on $X$ is called universal if every phylogenetic
tree on $X$ is a base tree for $N$. Recently, binary universal tree-based
networks have attracted great attention in the literature and their existence
has been analyzed in various studies. In this note, we extend the analysis to
non-binary networks and show that there exist both a rooted and an unrooted
non-binary universal tree-based network with $n$ leaves for all positive
integers $n$.
