Government agencies (such as the NSF and NIH) often include data sharing policies as part of their grant funding conditions. Understanding these conditions can ultimately save time and stress in the long run. Below are excerpts from NSF and NIH policies. See also a list from the Scholarly Publishing and Academic Resources Coalition (SPARC).
"Investigators are expected to share with other researchers, at no more than incremental cost and within a reasonable time, the primary data, samples, physical collections and other supporting materials created or gathered in the course of work under NSF grants. Grantees are expected to encourage and facilitate such sharing." [more from NSF]
"Data sharing is essential for expedited translation of research results into knowledge, products and procedures to improve human health.
The Final NIH Statement on Sharing Research Data was published in the NIH Guide on February 26, 2003. This is an extension of NIH policy on sharing research resources, and reaffirms NIH support for the concept of data sharing. The new policy becomes effective with the October 1, 2003 receipt date for applications or proposals to NIH." [more from NIH]
Publisher Data-Sharing Requirements
Journal publishers are increasingly mandating data sharing activities, sometimes more than certain funders. These data sharing requirements can also be required for an article to move to editorial review, and may even hold an article from publication.
Look for the data sharing requirements of any prospective publisher you wish to submit a manuscript to, and see if they recommend or support integrations with data repositories. See an example from American Geophysical Union.
Click the icons above to see specific policy examples from Nature and PLOS ONE.