A copy of every book published in the United Kingdom must be deposited with the British Library. This includes everything from the latest blockbuster through to the self-published history of the Jo Bloggs family. The British Library’s website provides the following succinct explanation of Legal Deposit:
“Legal deposit 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, to preserve the material for the use of future generations and to make it available for readers within
the designated legal deposit libraries”, (see http://www.bl.uk/aboutus/legaldeposit/).
From 6 April 2013 legislation pertaining to electronic publications came into force:
“From 6 April 2013, legal deposit also covers material published electronically, so that the Legal Deposit Libraries can maintain a national collection of
e-journals, e-books, digitally published news, magazines and other types of content.

The Legal Deposit Libraries (Non-Print Works) Regulations 2013 apply to any work published in offline media (on CD-ROM, microform etc.) in the UK, and to
any work published online:

“(a) if it is made available to the public from a website with a domain name which relates to the United Kingdom or to a place within the United Kingdom;
or

(b) it is made available to the public by a person and any of that person’s activities relating to the creation or the publication of the work take place
within the United Kingdom.” (see http://www.bl.uk/aboutus/legaldeposit/websites/faq/ukmaterial/index.html).
I am no legal expert. However my reading of (b) suggests that all UK authors should be providing copies of their electronic publications to the British Library. If you write in the UK this, to me indicates that the legislation applies (due to the activity of writing occurring in the UK). Of course Amazon and other ebook distributors may already be furnishing copies of electronic publications covered by the legislation to the British Library. However, in the case of Amazon at least I am not convinced that this is, in fact the case. Consequently the onus for providing electronic publications to the British Library appears to rest squarely on the shoulders of UK based authors.
Does anyone have any expertise in this field? I suspect that many authors, including myself remain somewhat confused regarding the legislation.

Kevin