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There are two major groups of content providers to the PubMed Central® (PMC) database: (1) peer-reviewed scientific and medical journals/publishers and (2) individual authors who are funded by NIH or other research funders that require funded articles to become freely available in PMC.

1. A few thousand journals voluntarily participate in PMC and have agreements to deposit the final published versions of some or all of their articles directly in PMC. 
There are three kinds of agreements:
  • Full participation – journal deposits all of its articles.
  • Selective deposit – journal/publisher chooses which articles to deposit. A number of publishers offer a program (for example Springer Open Choice, or Wiley Online Open) where an author has the option of paying a fee to make his/her article open access. The publishers generally then deposit these open access articles in PMC.
  • NIH portfolio – journal deposits just those articles that fall under the NIH Public Access Policy.
To establish if a journal participates in PMC, search the PMC Journal list. Once you locate your journal of interest in the table (example), you can see its participation agreement in the Participation Level column. The Free Access column provides information on the length of a journal’s embargo. Instead of finding a journal in the table, you may find it listed as a Search result for Special Collections Journals (example). The Special Collections tab in the PMC Journal List table will take you to the entire listing of of publisher programs and journals covered by selective deposit agreements. Note that there is no guarantee that one of these publishers will deposit a specific funded article in PMC. Authors should confirm the deposit agreement status with the publisher.

2. Many journals do not have any participation agreement with PMC. In this case, if you are NIH-supported author or principal investigator (PI) or an author or PI supported by other funders that have public access policies, you are responsible for ensuring that the accepted, peer-reviewed manuscript called for by a funding agency’s public access policy is deposited in the NIH Manuscript Submission (NIHMS) system. Only manuscripts that are covered by the public access policies of participating funding organizations can be deposited in the NIHMS.

For more details on PMC participation and PMC content see the following pages: