I\'ve encountered multiple third party .Net component-vendors that use a licensing scheme. On an evaluation copy, the components show up with a nag-screen or watermark or so
Almost everything about .Net licensing is explained here. No need to rewrite, I think.
It is better to exclude license files from project in source control, if you can. Otherwise, editing visual components may be pain in the ass. Also, storing license files in source control repository is not a need.
Hope this helps.