In my work we often talk about our customer's customer. For example, we might sell a widget to Acme, and they then provide widget-related services to Globex Corporation. I've been looking for a generic term for all of the Globexes out there, all of the companies that our direct customers (the Acmes) are selling to.
"Customer of the customer" is the best I've got, but it's pretty awkward. Is there a single word or a more pithy phrase out there?