These are likely biz dev / sales reps trying to drum up extra business, not lawyers. Calls and emails are easily ignored. I do it every day.
You ignore it, they move on to the next sucker. The people responding are the ones they'll work with.
It's also social media.
Online surveys.
Everybody and your servers needs to keep mum about it or otherwise you'll get a call.
You think I'm making this up? I've worked at two places where we were in contact with Oracle police because they thought we used (more of) their software.