Has anyone else come across this and what would you do?

I’ve been working SEO and Marketing for a large plumbing company and I came across a rival company using fake profiles to back link to their sites it’s ranking them higher for the key words that I want to rank for... after digging I’ve found out that this same “SEO” person is also working for the next two rival plumbing companies and doing the same thing... besides just reporting all of those fake profiles is there anything else I can do? It’s bizarre they are just taking random stock profile photos and making fake accounts on “about me, disqus, paper” etc. and linking their site just continues over and over...