Ein Aufsatz untersuchte die Präsentation von neuseeländischen Public-Domain-Büchern in einigen Repositorien:

http://firstmonday.org/ojs/index.php/fm/article/view/4975/4089

Google kümmert sich nicht um Meldungen, dass Bücher PD sind:

"Incorrectly blocked books from the sample were reported to Google Books in November 2013, along with biographical information proving public domain status. These titles are still blocked at the time of writing this paper in May 2014. A message was also sent to Google Books in November 2013 recommending changes to the wording of the landing page. Sending a message to Google Books’ support team required a Partner Program login account. A support team member advised that the issue would be investigated, however no changes have been implemented in response to this request. Follow–up correspondence with the Google Book’s support team was initiated in May 2014, and another support team member has advised that they would look into the issues raised. At the time of publication, no further changes have been made and all reported books remain restricted or blocked."

Besser sieht es (was ich bestätigen kann) bei HathiTrust aus: "An e–mail listing all incorrectly blocked books was sent to Hathi Trust in November 2013, along with biographical information showing their public domain status. In March 2014 a response was received from Hathi Trust, notifying that access had been enabled for all 11 of these books."

Und:

"The current estimation period of 140 years, used by Google Books and Hathi Trust, is far too conservative. If hosted under this policy, 47 percent of sample books would be restricted. This is despite the fact that all books with locatable biographical information were confirmed as being in the public domain for between 30 and 132 years."