My US clients often ask for a W8 or W8BEN to be filled out so that they don't have to withhold tax when they pay my invoices. I'm familiar with that process. Today I received a letter from an organization that claims to have money for me and wants a W9 from US citizens, W8 from non-US-citizens, and includes a W8BEN for me to fill out.
I've done a little due diligence on this company and they seem to be real, but I don't quite understand what the situation would be if they were not real. Armed with this form, what could someone do? If there isn't much downside I need less certainty about how real they are than if there is a significant risk.
(For those who don't see how a random stranger offering to send you money could ever be legit, they say it is photocopying fees related to material on which I hold copyright. I own a large amount of instructional material that could very well be copied outside the USA, so the assertions in the letter are believable. Web pages exist (I know they could be fake) in which other people say they got cheques from these people. Not saying this makes them real, just saying don't immediately dismiss it as ridiculous.)