Another interesting aspect of copyright is religion. Religion is one of the fundamental aspects of society. Religious texts are published, copies, and scrutinized by both true believers and critics. Can you imagine the Roman Catholic Church claiming copyright over the Bible?
Interestingly, the Authorised Version (or "King James Bible", as many people call it informally), which is the basis of most Bibles currently available in English, is under perpetual copyright in the UK*, though I believe no other jurisdiction recognises this, and it is made available at no charge by the Church Commissioners who administer the copyright on behalf of the Crown.
* - Technically, not perpetual; the author it deemed to be the Throne (i.e., the meta-physical "human" embodiment of the Sovereign - a natural person), rather than James I himself, so it has the copyright of life+70; until and unless the UK becomes a republic, the author is deemed to still be 'alive'. Who said IPR wasn't intruiging?
The reason that every major university maintains a department of mathematics is that it's cheaper than institutionalizing all those people.