Any wiki site has to deal with the questions of who owns the content created by its user community, and under what terms that content can be used by others. On NuMathWiki, the following rules apply:

• All content created on public wiki pages is licensed under the CC Attribution-Share Alike 4.0 International license. This is a common license in the same family as the one used by MathOverflow, Wikipedia, and many other sites with user-created content. By creating or contributing an edit to such a page, you should know that you are agreeing to have your work be subject to this license.
• By contrast, content created on private pages (that is, pages residing within a registered user namespace) is not licensed. All legal rights to the contents of such a page are held by its respective author(s), just as they are by default for any content created anywhere that isn't subject to a copyright license. Note that this remains true for private pages whose permissions have been set to make the page publicly viewable. It also remains true for private pages for which more than one user has edit permissions: for such pages, it is the responsibility of the authors to worry about ownership rights to the content they jointly created. NuMathWiki hosts the contents, but has no say in such matters.

An important consideration concerns migration of content from a private page to a public page. If the contents of a private page are posted on a public page, they become licensed. Therefore any user migrating content in such a way must first ensure that they have the agreement of all authors of the page to have the page content migrated to a public area of the wiki. (Such permission can be obtained for example through a discussion on the companion talk page of the private page, over email, or in any other reasonable way.)