Before you submit you latest paper, you post a copy on your personal Web site. Last year you posted your copy of a paper that included the revisions suggested by the reviewers. Your colleague down the hall takes the publisher's PDFs and adds them to his Web site.
Is that OK?
The answer is: it depends on the publisher.
How do you find out what a publisher allows? If you saved the copyright or license agreement that you signed, you can check the fine print. Or it might be easier to:
* Look on the publisher's Web site, in the section probably called Open Access or Author's Rights
* Check the Sherpa/Romeo Web site, at http://www.sherpa.ac.uk/romeo/ It gathers information from many publishers in one place, and groups them into categories based on whether you are may post papers before the review process (pre-prints), after the review process (post-prints), both, or neither.
Publishers may specify where you may post your paper, including your personal Web site, a repository at your institution, or a subject repository such as AgEcon Search. They may also note when you may post the article, with many having an embargo of 1 to 2 years for the post-review versions. Some require that you provide a link to the publisher's Web site where the "official" version is available.
For example, if you have a paper in Food Policy, published by Elsevier, you may put a pre-print on your Web site or a repository at your institution. You may also include your version of the paper with revisions (post-print), if you include the complete citation and the digital object identifier, the paper's unique identification number. In subject repositories such as AgEcon Search, you may post a pre-print. Details are at http://www.elsevier.com/wps/find/authorsview.authors/copyright#whatrights
Very few publishers allow authors to post the final PDF versions of their papers in any setting.
Conference papers and working papers are different. In most cases, authors retain the copyright, and you may post these works where ever you choose.
If you have questions about where and when you can post your papers, contact your local librarian. If you are interested in including pre-prints or post-prints on AgEcon Search, please contact us at firstname.lastname@example.org.