The National and University Library (NUK) is marking the 20th anniversary of Slovenia’s Legal Deposit Act, which entered into force in 2006. To mark the occasion, NUK highlighted the evolution of legal deposit, its role in preserving Slovenia’s cultural heritage, and the challenges facing the system today. Particular attention was given to musical heritage and the question of how to safeguard it in the digital age. As part of the anniversary programme, NUK exceptionally opened its storage facilities at Leskoškova cesta in Ljubljana to media representatives, offering a behind-the-scenes look at where a significant part of Slovenia’s national collection is preserved.
Legal deposit is one of the cornerstones of collecting and preserving the Slovenika collection —the national collection of library materials published in Slovenian, concerning Slovenia and Slovenians, or created by Slovenian authors. NUK has been building this collection since 1807. The modern Legal Deposit Act, which came into force on 18 October 2006, introduced significant changes by transferring the obligation to deposit publications from printers to publishers, producers and distributors, while also establishing a framework for the systematic collection of electronic publications.
Since 2008, NUK has also collected online publications, and since 2015, it has systematically harvested websites under the .si domain. Using web crawlers, the library regularly captures more than 5,000 selected websites and has also carried out several large-scale harvests of the Slovenian web domain. Today, the NUK Web Archive holds approximately 150 terabytes of data.
Marking the anniversary, NUK Director Dr Jana Kolar emphasised that preserving Slovenia’s cultural heritage is a shared responsibility. She thanked NUK staff for their daily work in building and safeguarding the national collection, as well as publishers, distributors, booksellers, authors and other content creators whose legal deposits make this work possible.
“Cultural heritage is not created only when something becomes old or historically significant. It is created every day—with every new book, music release and other publication. At NUK, we are proud to collect and preserve this creativity for future generations. That is precisely why we must also ensure suitable premises where we can store it safely,” said Dr Kolar.
Irena Sešek, Head of NUK’s Acquisitions Department, outlined the development of legal deposit and the key changes introduced by the Act. As a general rule, those required to deposit publications must provide NUK with four copies. For publications produced with public funding, the requirement rises to sixteen copies, although the legislation provides for certain exceptions. In addition to NUK, designated deposit libraries elsewhere in Slovenia and two libraries serving Slovenian communities in neighbouring countries also receive legal deposit material.
Looking ahead, Sešek stressed the need to adapt the legislation to a rapidly changing publishing landscape. “The law will need to respond to developments in publishing, from print-on-demand to new forms of online publications. Another major challenge is ensuring the long-term preservation of digital originals of printed publications, which would enable us to safeguard Slovenian publishing output even more effectively,” she said.
A Special Challenge: Preserving Digital Musical Heritage
Digitalization has profoundly transformed music publishing, making it increasingly difficult for NUK to track new releases and acquire legal deposit copies. While in 2006 it collected 767 different titles of music albums on physical media, current estimates show that in 2025 it acquired approximately 300. NUK received its first digital music album via legal deposit only in 2016, and over the following ten years, a total of just 177 digital music releases were collected.
“We don’t even learn about many music sound releases, which means we cannot even ask their publishers to submit a legal deposit copy. Publishing on a music platform does not guarantee permanent preservation,” warns Lidija Podlesnik Tomášiková, who handles legal deposit for music materials at NUK.
On the 20th anniversary of the Legal Deposit Act, NUK therefore aims to encourage musicians, record labels, and self-publishers to submit digital albums and singles as well.