I tend to think of poaching as a bit broader than that, but not just cold calling someone because you know they work at X.
For example, if someone leaves the company, and then there is a concerted effort to recruit other members of that team or based on their recommendation that is poaching. If you've signed an agreement that forbids this, and you actively take part in it, I think it is wrong; otherwise it is fine.
Alternatively, if you've engaged a companies services and then try and hire away the people doing the work to disintermediate the service providing compnay, that would probably count as poaching in my book too.
I consider both scenarios you described to fall squarely under my definition. Think about it, in both cases you learned about the prospects through their employment at said company.
For example, if someone leaves the company, and then there is a concerted effort to recruit other members of that team or based on their recommendation that is poaching. If you've signed an agreement that forbids this, and you actively take part in it, I think it is wrong; otherwise it is fine.
Alternatively, if you've engaged a companies services and then try and hire away the people doing the work to disintermediate the service providing compnay, that would probably count as poaching in my book too.