re: Is it legal to have a full time job and a consulting company at the same time?

I run a team of consultants and I don't care if they do side gigs. Several of them have asked me and been transparent about it. The main rules are just don't compete for the same clients, don't use company assets to do your side hustle, and don't let it affect your actual work. Aside from that, no one is going to care.