AS 1519:2018 Information and documentation – International Standard Book Number (ISBN)
5.1 A registrant element shall be allocated, upon application from the registrant of a qualifying monographic publication, from the ranges allocated to that registration group by the Registration Authority. Registrants who only intend to produce one publication may be assigned an ISBN from a common registrant element block reserved for that purpose within the ranges of that registration group.
5.2 As part of the application for an ISBN or ISBN registrant element, the registrant shall supply basic administrative contact details according to the specification and direction of the Registration Authority in order to allow the completion of registration into ISBN assignment records.
5.3 As part of the application for an ISBN or ISBN registrant element and each time an ISBN is assigned, the registrant shall supply metadata specific to the publication to which the ISBN has been, or will be, assigned according to the specification and direction of the Registration Authority (see Annex D).
5.4 Once an ISBN is assigned to a publication, that ISBN shall not be altered, replaced, or re-used.
5.5 If publishers are using intermediaries to generate products with different product form details or product forms with differing features or usage constraints of their e-books, then they should provide separate ISBNs for the intermediaries to assign to each separate product. If a publisher does not provide ISBNs to an intermediary for each separate product, then the intermediary may assign their own ISBNs in order to identify the products uniquely if they are made available in the supply chain. ISBN registrant elements will be provided to intermediaries for this purpose. ISBNs and related metadata shall be reported back to the publisher and to other bibliographic agencies along with the publisher’s original ISBN (if it exists), which shall also be included in order that sales data can be aggregated for the same title.