While searching something on the British Library website I came across a page that explained the legal requirement for depositing new publications. See below for a summary of this info. What is interesting from my point of view, is that it is a distribution that is legally required. Now motivated by collecting and giving access to the published works, but historically, it could be linked to controlling what is published and by whom. Copyright law came into being around the same time in the 17th century, with a double purpose. Control by the state and a commercial motive for the publishers . Authors, artists, publishers and the state have been dancing around freedom of speech, copyrights and distribution ever since. Who said “manuscripts don’t burn”? Bulgakov did, but they did burn in the 17th century, and are still burning today…
Copy from British Library website:
Introduction and background
Legal deposit for printed books and papers has existed in English law since 1662. It helps to ensure that the nation’s published output (and thereby its intellectual record and future published heritage) is collected systematically, and as comprehensively as possible, both in order to preserve the material for the use of future generations and to make it available for readers within the designated legal deposit libraries. (…)
The legal deposit system also has benefits for authors and publishers:
- Publications deposited with the British Library are made available to users in its various Reading Rooms, are preserved for the benefit of future generations, and become part of the national heritage.
- Publications are recorded in the online catalogue, and will remain an essential research tool for generations to come.
- Most of the books and new serial titles are listed in the British National Bibliography (BNB), which is used by librarians and the book trade for stock selection, is available on CD-ROM in MARC Exchange formats, and has a world-wide distribution.
Legal deposit in the UK is governed by the Legal Deposit Libraries Act 2003. (…) See ‘External links’ for both Acts.
Deposit of printed publications
The right of the British Library to receive one copy of every publication distributed in the United Kingdom or Republic of Ireland is based on the Legal Deposit Libraries Act 2003 in the UK and the Copyright and Related Rights Act 2000 in the Republic of Ireland.
Within the terms of the Legal Deposit Libraries Act 2003, ‘publisher’ is to be understood as anyone who issues or distributes publications to the public. Items published in the United Kingdom and in Ireland are liable for deposit, as are items originally published elsewhere but distributed in the United Kingdom and in Ireland. The requirement for deposit remains, irrespective of the place of publication or printing, the nature and size of the imprint, or the extent of its distribution.
All printed and microform publications (with the exception of newspapers) should be sent to:
Legal Deposit Office, The British Library, Boston Spa, Wetherby
West Yorkshire LS23 7BY
 Patterson, L. Ray, “Copyright and “the Exclusive Right” of Authors” (1993). Scholarly Works. Paper 343. See p.8-13.
http://digitalcommons.law.uga.edu/fac_artchop/343 [Free full text pdf download]