id	author	title	date	pages	extension	mime	words	sentence	flesch	summary	cache	txt
crl-16582	Wilkin, John P.	How Large Is the “Public Domain”? A Comparative Analysis of Ringer’s 1961 Copyright Renewal Study and HathiTrust CRMS Data	2017-04-19	18	.pdf	application/pdf	8954	342	52	Estimates of the size of the corpus of public domain books published in the United States from 1923 through 1963 have been inflated by problematic assumptions, and we should be able to correct mistaken conclusions with reasonable effort. U.S. law required compliance with certain rules for works published through most of the 20th century, and many books published in the United States during that period entered the public domain as a consequence of failure to comply with those rules.1 One of those rules, a requirement that the copyright holder for a work published between 1923 and 1963 renew the copyright of the work 28 years after it was published, was the subject of an important Copyright Office study discussed here.2 Many cite this study to suggest that 93 percent of books published in the United States during this period are in the public domain.3 Recent work by the IMLS-funded CRMS project, a HathiTrust project focused on books digitized from research libraries, found a significantly smaller percentage of public domain books for the same period, approximately 50 percent.4 The significant difference in the numbers established by these two efforts is puzzling.	cache/crl-16582.pdf	txt/crl-16582.txt