text: ***5. Examining approaches to building a books data***
  ***commons***
  
  There are many possible permutations for building a books data commons. To structure our 
  exploration, we focused on two particular tracks, discussed below. We chose these tracks 
  mindful of the above legal issues, and because there are already existence proofs that help 
  to illuminate tradeoffs, challenges and potential paths forward for each. 
  
  *5a. Public domain and permissively licensed books*
  
  **Existing Project Example : The Pile v2**
  27 
  
  In 2020, the nonproﬁt research group EleutherAI constructed and released The Pile — a large, 
  diverse, open dataset for AI training. EleutherAI developed it not only to support their own 
  training of LLMs, but also to lower the barriers for others.   28 
  
  Along with data drawn from the web at large, The Pile included books from three datasets. 
  The ﬁrst dataset was the Books3 corpus referenced at the outset of this paper. The second 
  and third books datasets were smaller: BookCorpus2, which is a collection of 17,868 books 
  by otherwise unpublished authors; and a 28,752 books in the public domain and published 
  prior to 1919, drawn from a volunteer effort to digitize public domain works called Project 
  Gutenberg. 