End-user/registrant different than purchaser

We recently purchased a named-user license via a third-party vendor and received a serial number. We supplied the name of one of our employees during the ordering process, The license is meant to be used on behalf of a client, and therefore the client should be the end-user/named-user for licensing purposes.

If we give the serial number to our client and have him register and download the license file, will this suffice to make him the end-user? Or was the serial number tied to us in some way when it was generated?

Thanks, Valerie