Limit folder share to external clients

We are a software house, currently we signed up box.net, and we would like to share out different folders based on client,
e.g.
my-box.net account
+ ClientA folder
+ ClientB folder

and our client A, B are not box’s subscribers. Hence, is it possible for us to share any credentials (similar to SFTP) and allow client A, B to access their folders respectively and pull out their files?