Copyright laws, US and German, can be comprehensive and sometimes confusing. However, I think in this case the answer to your question is on the introduction page of the Blue Books. It states that All rights are reserved. No doubt that includes copyright.
A quick search shows that German copyrights are for the life of the author + 70 years. In the US it's 95 years from publication for works published 1964–1977.
So, not expired.
Yes, there are pdfs of the owners manuals posted, and BMW no longer supplies the Blue Books, but BMW corporate can be sticky when it comes to use of their name.
One of the forum members was posting 3D scans of some interior parts online and the description indicated theses were for the BMW E9. He got a take down notice from BMW saying his description might confuse people into thinking that this was an OEM part, which is hard to believe as the site was specifically for listing 3D printed parts and the language of the post only stated that it fit those model cars.
If you, and maybe a forum admin, write to BMW and ask if the Blue Books can be posted here they will give you written permission. But to post them without that would be risky to the forum, which none of use would like to see impacted negatively. Yeah, maybe only a take down letter, but maybe much more. The son of a friend of mine who was visiting Germany decided to download some bootlegged movies and the German systems detected it, found him quickly and they had to pay quite a large fine. Since our site is available in Germany, that might be a problem without permission to post them.
I would like to have PDFs of the Blue Books as searching would be faster than the paper version I have, but we must be careful to stick to the rules.
