The News Media Alliance (NMA) recently reported that the U.S. Copyright Office and Library of Congress are now requiring publishers to submit copies of newspapers in pdf format for registration with the Copyright Office and required deposits with the Library of Congress.
According to NMA, PDF submissions are required immediately. Publishers may additionally submit voluntary microfilm deposits if they are worried about not complying with the PDF requirement. The copyright offices will allow the voluntary deposit of microfilm (alongside the mandatory deposit of PDF) until December 31, 2019.