Legal deposit for a book in Spain serves to preserve publications issued in the country. It is governed by Law 23/2011, as amended by Law 8/2022, and is not the same as obtaining an ISBN.
Who must apply for the number?
For a work published in a tangible format, the publisher is normally responsible. The law specifies substitute responsible parties in certain circumstances, including when the publisher has not applied.
When must it be requested and deposited?
The legal-deposit number must be requested before production or printing ends. Materials subject to the requirement must be deposited before the work is distributed or sold.
Where is it processed?
The procedure is handled by the legal-deposit office designated by the relevant autonomous community, normally according to the publisher’s registered office and the applicable rules.
How many copies must be supplied?
The quantity depends on the type of publication. For first editions and reissues of paper books, the consolidated law provides for two copies; where the pre-print digital file exists, the publisher must also deposit it in the format used. Other categories and print-on-demand publications can have specific provisions, so confirm the requirements with the relevant office.
Where should the number be printed?
It must appear in a visible, identifiable place. For books, it must be on the same printed sheet as the ISBN, if there is one, and may appear on the reverse of the title page or on the back cover.
Legal deposit versus ISBN
Legal deposit preserves the published heritage; an ISBN identifies a particular book edition for commercial and cataloguing purposes. The procedures are not interchangeable.
Official source
Consult the consolidated Spanish Legal Deposit Act in the BOE and the current instructions from the relevant autonomous-community office before submitting materials.
Frequently asked questions
Must the author always apply?
No. Responsibility generally depends on who is acting as publisher.
Is it the same as an ISBN?
No.
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