I was talking with someone today and this discussion came up.
Suppose you purchase some software and X user licenses for it. You then want to install another instance of the software, however the company tells you that you need to buy another X licenses to use the 2nd installation. Is it ethical to duplicate the licenses since the same X users are going to be using them? (the security on the program we were talking about is not very good)
EDIT Licenses are per-concurrent-user. In this situation users would (generally) not be logged into both installations at once. Regardless, we would keep the number of users logged in between the two installations limited to the number of licenses we purchased.