Just to make absolutely sure; Charity usage rules

I just want to make absolutely sure that I understand the rules for deploying SpywareBlaster free of charge in an office environment. The rules state that a registered charity can use SpywareBlaster for free. What exactly is meant by the term "registered charity"? Does it imply simply being a 501 (c) (3) non-profit organization or does it necessitate a certain standard of benevolence be met? I work in a 501 (c) (3) organization and would like use SpywareBlaster on the client machines, however the term "charity" doesn't exactly fit my organization (we're not like a homeless shelter, rehab center, or food bank).

Furthermore, does proof of an organization's charity/non-profit status need to be shown or is this all built on good faith?

Thanks in advance,
"StandardGreen"