PMC International (PMCI) is a collaborative effort between NIH and NLM, the publishers whose journal content makes up the PMC archive, and organizations in other countries that share NIH's and NLM's interest in archiving life sciences literature. The long term goal of PMCI is to create a network of digital archives that can share all of their respective locally deposited content with others in the network. There are three primary reasons for doing this:

• The probablity of an archive surviving over the long term is greater if there are working copies of the archive in regular use at multiple sites around the world.
• A producer or funder of research literature often will be more inclined to make the primary deposit of its material to a locally or regionally affiliated archive, rather than to one operated elsewhere in the world.
• Each site can integrate the journal articles in the archive with related material, such as national or regional practice guidelines, that has particular significance to its users.

NLM currently supports two PMCI centers: UKPMC and PMC Canada. Collaboration with each center is based on a formal agreement between the NLM and the center's sponsors concerning the management of the archive. This agreement protects the rights of those who deposit content in PMC and ensures the integrity of their content by requiring each center to use NCBI's pPMC software, described below. It also ensures that users will always have free access to the content. (See the prototype agreement.)

UKPMC

UKPMC is sponsored by the Wellcome Trust and several other major research funders in the UK, and became operational in January 2007. At present, UKPMC receives all of its final published articles directly from the U.S. PMC archive. It also accepts and processes author manuscripts of journal articles funded by various agencies in the UK and makes them available to U.S. PMC and PMC Canada.

PMC Canada

PMC Canada became operational in October 2009, under an arrangement with NLM and NCBI similar to that for UKPMC. PMC Canada represents a partnership between the Canadian Institutes of Health Research (CIHR), the National Research Council's Canada Institute for Scientific and Technical Information (NRC-CISTI), and the NLM. Like the UKPMC, PMC Canada receives all of its final published content through the US PubMed Central. In Spring 2010 it will begin taking in CIHR-funded author manuscripts which it will make available to the U.S. and UK sites.

Content Available at International Sites

UKPMC and PMC Canada include all PMC content - with the exception of final published articles from publishers who have not given permission for their content to be deposited in one or both of these international sites. Since July 2006, all PMC Participation Agreements have included permission to make a participating journal's PMC content available to UKPMC automatically. Publishers participating in PMC prior to July 2006 were asked for permission to deposit their content in UKPMC, and most agreed to it.

Similarly, since June 2009, all PMC Participation Agreements have also included permission to make a participating journal's PMC content available in PMC Canada automaticially. Publishers participating in PMC prior to June 2009 were asked for permission to deposit their PMC content in PMC Canada. Again, most have agreed to it.

Future PMCI Centers

When appropriate, NLM expects to expand the PMCI network to include centers serving other countries or regions. NLM will agree to a new center only if the following conditions are met:

• The new center must be sponsored and managed by a national or international agency with a committment to building and managing the archive for perpetuity. It may be a government agency, or a not-for-profit organization at an equivalent national or international level, formed by non-commercial entities such as universities, research institutions, funding agencies, or professional societies.
• The new center must attain an operational level that meets standards defined by the NLM, and the sponsors and managers agree to maintain that level into the future.
• The new center must sign an agreement with NLM concerning the management of the archive. This agreement protects the rights of those who deposit their content in PMC, ensures the integrity of their content, and ensures that users will always have free access to the content. (See the prototype agreement.)

When NLM decides to support another PMCI center, all publishers with existing PMC Agreements will be asked for permission to redistribute content to the new center. New PMC Agreements will automatically incorporate permission to distribute content to the new center.

Portable PMC (pPMC)

Portable PMC (pPMC) is a software package developed by NLM's National Center for Biotechnology Information (NCBI). It is derived from the software used to operate the U.S. PMC system at NLM. It allows PMCI centers to import data from PMC, build a local database, and display the content of each article in the PMC style. The pPMC software itself does not include any rights to the PMC content.

Portable NIHMS

The NIH Manuscript Submission System (NIHMS) was developed by NCBI to facilitate the submission of final, peer-reviewed manuscripts to NIH in support of NIH's Public Access Policy. NIHMS users upload manuscripts in a wide range of electronic word-processing formats, and these manuscripts are subsequently processed and deposited in PMC.

Portable NIHMS (pNIHMS) is a portable version of the NIHMS software, also developed by NCBI. The PMCI centers use pNIHMS for local intake of manuscripts and their subsequent deposit in PMC.