PubMed Central ( PMC) is a freely accessible database containing literature from medicine, biology and related fields in full text. PMC was built by the United States National Library of Medicine and is funded by the National Institutes of Health ( NIH). The number of available products has exceeded 2.9 million in 2013 and rising steadily.
Since 2008 in the U.S. by law (HR 2764 ) that all research results that come about through grant from the NIH, will be published within twelve months of original or as a copy in PMC. A period of six months shall be granted some magazines as embargo. The law is being discussed in the context of the debate on Open Access.