That's a good point actually. It's one thing to pay for someone else to make/edit a map for you, but that person should ideally keep the credit for doing so. Other people should be allowed to know that a given map was a commissioned piece of work, including who commissioned it and who actually did the work.Is this something they're demanding as part of the agreement with you? Because you still created the map, regardless of whom for, and I've never heard of someone objecting to letting the creator retain ownership of the thread. It's not like they're the ones who are going to be responsible for updating it in the future, either, and if you hand the download over to them, you won't be able to update it anymore.