I've noticed for some time that ProQuest PDF copies of historical newspapers, even from the 19th Century, are marked at the bottom of each page "Reproduced with permission of the copyright owner. Further reproduction prohibited without permission."
This doesn't make much sense to me for contents that would themselves be in the public domain due to copyright expiration.
After searching, I see this statement on a ProQuest-owned site, claiming that even for documents in the public domain, "the electronic versions of these texts are the copyright of ProQuest Information and Learning".
Are the PDFs themselves truly copyrightable if they add no creative content, other than the copyright notices? Can they plausibly claim that even pixel-perfect screenshots of the PDFs are somehow in violation of their copyrights, when the original scanned documents would no longer be in copyright?