On February 22, 2013, in a policy memorandum, OSTP Director John Holdren directed Federal agencies with more than $100M in R&D expenditures to develop plans to make the published results of federally funded research freely available to the public within one year of publication and requiring researchers to better account for and manage the digital data resulting from federally funded scientific research. For more information, visit: http://www.whitehouse.gov/administration/eop/ostp/library/publicaccesspolicy
The following links contain specific information and requirements for public access and data sharing plans for certain U.S. agencies.