Plan S

• All publications must be published under an open licence, preferably the Creative Commons licence CC BY 4.0.
• As secondary alternatives, they accept the use of the CC BY SA 4.0 licence, and use of the public domain dedication, CC0.
• cOAlition S members may approve the use of the CC BY ND licence for individual articles, provided that this is explicitly requested and justified by the grantee.
• All scholarly articles that result from research funded by members of cOAlition S must be openly available immediately upon publication, without any embargo period.
• Author should use PIDs for authors (e.g., ORCID).

Compliance with Plan S can be ensured in three ways: 

• Use of persistent identifiers (PIDs) e.g. DOI, URN, Handle,
• Deposition of content with a long-term digital preservation or archiving programme,
• High-quality article level metadata in standard interoperable non-proprietary format, under a CC0 public domain dedication. Metadata must include complete and reliable information on funding provided by cOAlition S funders (including as a minimum the name of the funder and the grant number/identifier).,
• Journal should be registered in DOAJ (Directory of Open Access Journals).
• Transparent costing and pricing: information on the publishing costs and on any other factors impacting the publication fees must be openly available on the journal website/publishing platform,
• Direct deposition of publications (in a machine-readable community standard format such as JATS XML, and including complete metadata as described above) by the publisher into author designated or centralised Open Access repositories that fulfil the Plan S criteria,
• Linking to data, code, and other research outputs that underlie the publication and are available in external repositories,
• Open Access journals must not have a mirror/sister subscription journal with substantial overlap in editorial board to avoid business models charging for both access and publication

• The repository must be registered in the Directory of Open Access Repositories (OpenDOAR) or in the process of being registered,
• Use of persistent identifiers (PIDs) e.g. DOI, URN, Handle,
• High quality article level metadata in standard interoperable non-proprietary format, under a CC0 public domain dedication. This must include information on the DOI (or other PIDs) both of the original publication and the deposited version, on the version deposited (AAM/VoR), and on the Open Access status and the licence of the deposited version,
• Helpdesk for users,
• Continuous availability (uptime at least 99.7%).

• cOAlition S emphasises the need for high-quality journals, therefore requiring journals/platforms to have a solid system in place for review according to the standards within the relevant discipline and guided by the core practices and policies outlined by the Committee on Publication Ethics (COPE). Details must be openly available on the respective journal and platform websites. In particular, payment of publication fees or waiver status must not in any way influence the editorial decision-making process on the acceptance of a paper. 

source: Plan S Principles and Implementation