Keeping world-leading international law resourceÌýopen access

30 March 2026
1 min read

°Õ³ó±ð   has reached its goal for renewals and will continue to publish on a Subscribe to Open model, through to at least March 2027.

°Õ³ó±ðÌýMax Planck Encyclopedia of Public International LawÌýisÌýthe leading resource in the field,ÌýcontainingÌýpeer-reviewed articles on every aspect of international law—aÌýdisciplineÌýwhichÌýprovides a common legal framework for the whole world.

By convertingÌýthisÌýcomprehensive, analytical resourceÌýtoÌýan open access,ÌýSubscribe to Open model,ÌýweÌýhave made it possible for students, scholars, practitioners, and governmentsÌýworldwideÌýto access this content freely without financial barriers. 

Subscribe to Open in practiceÌý

°Õ³ó±ðÌýMax Planck Encyclopedia of Public InternationalÌýLawÌýisÌýOUP’sÌýfirst experiment with the Subscribe to Open model – a modelÌýtypically applied to journals rather than books. Thanks to the support of ourÌýinstitutional and libraryÌýcustomers, this valuable content is freely accessibleÌýto allÌýfor a second year.

As a result of theÌýSubscribe toÌýOpen model, usage of the encyclopaedia has increasedÌýsubstantiallyÌýfromÌý2024 to 2025:

  • An increase in usage by 1,291%
  • An increase in usage from low- and middle-income countries byÌý556%Ìý 
  • Access from users inÌý235  different territories around the world, anÌýincreaseÌýfrom 199,ÌýincludingÌýallÌý196 United Nations member states.

Professor Anne Peters, Director at the Max Planck Institute for Comparative Public Law and International Law, Heidelberg, and General Editor ofÌýthe Max PlanckÌýEncyclopediaÌýof Public International Law, said:

“We are delighted to have this opportunity toÌýparticipateÌýin a pioneeringÌýopenÌýaccessÌýproject, particularly in view of the foundational role played by the Max Planck Society in launching the move towards open scholarship.ÌýOpenÌýaccessÌýcan contribute to epistemic justice and pluralism—and what we call “encyclopaedic knowledgeâ€� should not only be distributedÌýfreely, butÌýalso be built up from a globally diverse set of standpoints.â€�Ìý

Rhodri Jackson, Director of Open Access Publishing and Strategy, shared:

“Innovation in open access models is in line with our mission: not only to publish excellent research and scholarship but to make it available worldwide. We are committed to learning from all our initiatives—successful and less successful—and to sharing our results transparently. The first year of Subscribe to Open for the Max Planck Encyclopedia of Public International Law has been a great success and we’re excited to see what happens in year two.�

WhileÌýwe have reached our goal for renewals this year, we still need to reach our renewal goals annually to keep this resourceÌýopen access. By renewing your subscription, you help to ensure that this valuable resourceÌýremainsÌýopen and accessible to all, year after year.

Find more information, including about renewals, .

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