How does a company get control of a Facebook group about itself?

[dj]

I am compiling a helpful document to guide businesses through some aspects of online reputation management and am not 100% sure on some aspects of applying this to Facebook groups. For example, say current or former staff of a company have set up a public Facebook group in the company name (or called something like "X company staff zone" etc) and the things posted in there aren't exactly what the business would want clients or potential clients to associate with them, what can they do?