Join forces with us to ensure preservation of digital content

Since 2008, academic libraries and scholarly publishers have collaborated to provide a global digital archive to ensure the long-term survival of digital scholarly content.

Libraries, entrusted with preserving scholarly content in the digital age, often struggle with uncertainties about its long-term accessibility. CLOCKSS steps in as a reliable partner, offering a robust preservation archive endorsed by the Center for Research Libraries. Employing top-tier LOCKSS software, CLOCKSS stores content securely across its global network, resilient against various threats, ensuring uninterrupted access for future generations.

Today, in partnership with supporting libraries and participating publishers, CLOCKSS operates 12 archive locations hosted at leading academic institutions worldwide. Together, we are able to safely, and securely, preserve the authoritative versions of journal articles, books, and supplementary materials and metadata. Using LOCKSS opensource preservation software, CLOCKSS ensures that the digital content remains healthy, so that if the content ever needs to be available for access CLOCKSS is able to retrieve it, migrate it to new formats, and deliver it.


Governed by leading academic libraries and publishers, CLOCKSS commits to affordability, enabling participation from libraries of all sizes and budgets, ensuring the collective preservation of scholarly knowledge for generations to come.

Security for digital scholarly content

CLOCKSS is a trusted long-term digital archive. Our Trustworthy Repositories Audit and Certification (TRAC) audit by the Center for Research Libraries resulted in a score of 14 out of 15, including perfect scores for Technologies, Technical Infrastructure, Security and for Organizational Infrastructure. This is the highest score ever awarded.

CLOCKSS Value Proposition to Supporting Libraries

Preservation is content insurance! When scholarly content transitioned to electronic delivery, academic libraries realized that they no longer hold copies of the content to preserve. This means the content from publishers is not guaranteed to always be accessible to the library’s users. When libraries support CLOCKSS they safeguard the long-term survival of digital content in their libraries or published by their authors, maximizing return on investment and ensuring use for future generations.

CLOCKSS makes content available Open Access

CLOCKSS offers global scholarly communities perpetual access to content, as soon as it becomes available, under Creative Commons licenses. As the only dark archive that assigns a Creative Commons license to all digital content as soon as it becomes open for access, CLOCKSS benefits the greater global scholarly community by enabling permanent Open Access to abandoned and orphaned publications. As a result, recovered content becomes perpetually available to anyone with Internet access.

CLOCKSS is open infrastructure

The CLOCKSS Archive is a key open infrastructure service, aligned with the POSI principles, and participates in standards development initiatives.

CLOCKSS is committed to biblio-equity and research integrity practices

CLOCKSS is committed to Diversity, Equity, and Inclusion (DEI) in its archival practices and upholding research integrity. By ensuring a diverse range of scholarly content is preserved, CLOCKSS promotes equitable access to knowledge across various disciplines, cultures, and perspectives. CLOCKSS upholds research integrity by maintaining the authenticity, accuracy, and accessibility of preserved content, ensuring that it remains unaltered and trustworthy for future researchers.

CLOCKSS is governed by the community

CLOCKSS is a free-standing charitable, non-profit organization in the U.S. Its Board of Directors is comprised of twelve leading academic libraries and twelve leading academic publishers. The Board discusses and sets policies, practices, and prices.

CLOCKSS is committed to keeping fees affordable

We enable libraries and publishers of all sizes and budgets in all parts of the world to participate in CLOCKSS. Low operating costs make it possible to keep this commitment.


To join CLOCKSS or to find out more, please contact Alicia Wise, Gali Halevi, or Kim Smilay at

CLOCKSS 2024 Library Support Rates

Libraries Materials Budgets - 2024 Annual Contribution
Under $1 million $520.00
$1 - 2 million $690.00
$2 - 3 million $1,380.00
$3 - 4 million $2,080.00
$4 - 5 million $2,770.00
$5 - 7 million $3,460.00
$7 - 9 million $4,835.00
$9 - 11 million $6,225.00
$11 - 13 million $7,610.00
$13 - 15 million $8,995.00
$15 - 20 million $10,370.00
$20 - 25 million $13,830.00
Over $25 million $17,295.00


Please download and complete the Supporting Libraries Form.

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