Berlin Declaration
Open Access to Knowledge in the Sciences and Humanities
The pertinent passages:

“Open access [means]:

“1. free... [online, full-text] access

“2. A complete version of the [open-access] work... is deposited...
        in at least one online repository... to enable open access, unrestricted distribution, [OAI] interoperability, and long-term archiving.

“[W]e intend to... encourag[e].. our researchers/grant recipients to
   publish their work according to the principles of... open access.”