Public Domain Check - Confirming the author has died at least 70 years ago
Summary
The goal of the check is to avoid uploading non-public domain data.
The digitized documents obtained from the Danish Royal Library have a range of publishing dates from 1750 to 1930.
According to Danish law 70 years must pass after the death of the author(s) in order for these documents to become part of the public domain.
Based on this, the data can be separated to 3 distinct groups:
- Published before 1833: Even if the longest living human in modern history wrote that as soon as they were born, they still died more than 70 years ago
- Copyright info supplied: The Danish Royal Library provides meta data on several of these documents, in which they claim the writing is indeed part of the public domain
- The rest: Documents where public domain status has to be investigated
To confirm whether a document is part of the public domain or not, the author(s) indicated in the meta data were matched against a database of potential Danish authors. Both their full names and potential abbreviations were used. A document was marked as being in the public domain if:
- All authors were matched to at least one name in the reference database
- All of these matches had complete biographic information in the reference database
- The author(s) died at least 70 years ago
- The author(s) have been born at least 18 years before the publication date
It must be noted, that the digitization took place over the course of several years, the provided meta data mostly follows a standard layout, but some documents might differ in that regard. This can be a potential source of errors.
IMPORTANT: In case some non-public domain document is found in the dataset, please let us know
The matched authors and written media is available for reference in .parquet format as public_domain_data.parquet
The list of only the filenames of the selected works (used in the extraction process, and is probably less important to outside parties) is available as public_domain_files.txt
Sources
Potential authors were gathered using Web Scraping
Logic
The flowchart is for a broad understanding and is not a fully accurate representation.
The whole python script is provided for reference as select_pd.py
Made with:
- python 3.12.10
Required libraries for running: