About SNBVEs and digital publications
SNBVEs are not only for digital books; in fact it is of no relevance in what medium a publication is made available. Provided it is text-based, available to the public and a one-off (not serial) publication then it will qualify for SNBVE assignment. SNBVEs should be used to identify each separate digital publication (including apps) and guidance on how to do this is given here.
What is a separate digital publication?
In order to reach the widest possible market, a publisher or retailer may make a particular e-book title available as multiple product options. Although the editorial content will be the same, if a specific device or software is required to read the e-book or different usage constraints that control user functionality are offered (e.g. copy, print, lend etc.) then each separate version will be a distinct product. Each distinct product that is available must be identified by its own SNBVE as it is a separate publication. Thus, a separate publication is normally defined by a combination of product form features or details and usage constraints.
What if the e-books are all in the same format (e.g. EPUB)?
If the different versions are in the same format and use the same DRM software (e.g. Adobe ACS4) with substantially the same usage constraints and are interoperable on different devices or software, then a single SNBVE should be used. If, however, the same DRM software is used on two versions but with significantly different usage constraints (e.g. one allows printing but the other does not) then each version should have its own separate SNBVE.
If proprietary DRM is used that ties a version to a specific platform, device or software then, if SNBVEs are assigned, separate SNBVEs should be used for each such version.
How are “master files” treated?
Publishers often provide a single master file to a conversion service but may not always specify the different combinations of file format and DRM which the conversion service will provide to retailers. Unless it is also being made available to the public in exactly the same form as the master file (i.e. unchanged file format and without DRM applied) then you should not give an SNBVE to the master file. However, you should assign separate SNBVEs to each version that is subsequently generated by the conversion service. If your legacy computer system requires an SNBVE to identify a master file, then this should be kept as a purely internal identifier to avoid the possibility of several different versions carrying the same SNBVE.
What if publishers don’t assign separate SNBVEs for each version?
Publishers should provide their conversion service with all the SNBVEs that they will need to identify each of the versions that they will produce. If a publisher will not provide SNBVEs to intermediaries for this purpose then, as a last resort, intermediaries may assign their own SNBVEs. SNBVE agencie will provide SNBVE prefixes to intermediaries for this purpose. In this case SNBVEs and related metadata should be provided back to the publisher and to the national SNBVE agency and other bibliographic agencies.
Note that the assignment of an SNBVE has no implications for rights ownership.
What if e-book devices don’t support different features such as type size, text to speech, bookmarking, colour, etc? How does this affect the assignment of SNBVEs?
Although the content, file format and DRM usage constraints will be set by the publisher or intermediary for a particular e-book and delivered to the user in this way, it is still possible that the user experience may vary according to the device or software of the user. When the variation results from limitations of the capability of the device or software used to read the e-book then this does not impact on SNBVE assignment. The same SNBVE should be used because the same product is being delivered each time.
Note that provision of mono or colour images in separate e-publications intended respectively for mono or colour devices constitutes a change of content – and therefore of SNBVE. However if colour images are provided, but a particular device has only a mono display, that is simply a device limitation and does not imply a second SNBVE.
What about enhanced e-books?
When an e-book is available in enhanced form and includes audio, video or other additional content, it will qualify for SNBVE. If the e-book is also available separately without these extra elements then these are different products and should therefore have separate SNBVEs.
Can e-book “apps” (e.g. applications for iPhone, Android etc.) have SNBVEs?
Yes, provided that there is significant textual content and as long as the book (as it is a digital product) does not have a physical version. An e-book app is simply a combination of textual and other content and software. If the software element changes (e.g. it is targeted on different operating systems), then each version should have a separate SNBVE. If the app is only made available through a single source, then SNBVEs may not be necessary.
What about different types of DRM?
It is possible that an e-book may be available at the same time either with no DRM at all, with different DRM software or with “social” DRM applied. If the “social” DRM version does not intrude significantly on the user’s experience, does not enforce any usage constraints and is transparent to the user then it need not be given a separate SNBVE from the version with no DRM at all. However, if the different types of DRM are used to enforce different usage constraints or enable/disable certain features, then separate SNBVEs must be assigned.