Digital preservation

The Royal Society has partnered with CLOCKSS and PORTICO to preserve our journal content. Both are not-for-profit services committed to the long-term preservation of digital content, including e-journals, e-books, and retro-digitised historical collections.

By archiving within these two organisations, we are ensuring that all our content remains accessible to future scholars around the world, no matter what happens to the Royal Society.

Controlled Lots of Copies Keeps Stuff Safe (CLOCKSS)

CLOCKSS is a collaborative project between 14 of the leading publishers and 34 institutional libraries to provide a 'dark archive' to ensure the long term survivability of (ultimately all) web-based scholarly material.

It uses the LOCKSS technology to archive everything from the participating publishers. Content is supplied to CLOCKSS either in source or presentation format and the archive is kept 'dark' until a 'trigger event' (such as the catastrophic failure of a publisher's platform or the publisher going into liquidation) at which time it is made freely accessible.

Each participating publisher and library in CLOCKSS has a representative on the Board which votes on whether any break in accessibility to content is merely temporary or constitutes such a 'trigger event' allowing that archived content to be made available. In such circumstances, content is made free to everyone, not just participating libraries.


PORTICO is a similar not-for-profit organisation launched in 2005 and based upon an earlier system set up by JSTOR in 2002 with a grant from the Andrew W Mellon Foundation. Source files are supplied by publishers and 'normalised' into a standard archival format (based on the open standard Journal Archiving and Interchange DTD) which can reliably be managed over the long term. In addition to merely archiving the content, PORTICO will actively curate it by transitioning the material from 1 file format to another as technology changes and as file formats become obsolete.

Access is granted to the archive in response to a verifiable 'trigger event' in a similar way to the CLOCKSS process. There are currently 82 participating publishers.