For a proof for an article I would need the following result:
If $A_\Gamma$ is an Artin group such that the $K(\pi,1)$-conjecture holds for it and $\Gamma'\subset\Gamma$ is an induced subgraph, then the $K(\pi,1)$-conjecture holds for $A_{\Gamma'}$.
I've searched in all the references I know about this conjecture, but none of them seems to prove this fact. My question is if you know whether this has been proved or not, and in case it its where I can find it.
Thanks in advance.