Open Access as a concept can apply to either a work, or a process. I believe that this distinction would help in making our definitions of open access more precise. This distinction is not quite the same as the distinction between noun and verb.
Open Access work: a work can be said to be open access when it is, at minimum, free for anyone, anywhere to read online (gratis open access), or, better yet, free for anyone to re-use (libre open access). A work that has been closed access for the full term of copyright, can be made open access after it enters the public domain.
Open Access process: a process, such as publishing, can be open access as well. In this sense, it makes sense to reserve the term open access for full open access publishing, where a work is made open access (gratis or libre) as part of the publishing process, with no delay.
One way to understand this distinction: when a journal employs a transitional strategy such as free back issues, it makes sense to say that the journal is NOT open access, but rather that it uses a free back issues strategy. The issues and the articles, as they become free, however, ARE open access. That is, it is the works that are open access, even though the journal / publisher is not OA.
There is probably a better way to articulate this distinction; if anyone is willing to undertake this task, please do! To facilitate reuse of this work, this particular post is CC-BY.
Precision in OA definitions is extremely important, partially because of the potential for confusion arising from the many changes in scholarly communications (and indeed, in our world) taking place all at once, and also because of lobbying efforts by those opposed to open access, which often take the form of opposing something other than what open access is (a good example being the Conyers bill in the U.S., which you can read about on Open Access News).
This is a bit of reflection to prepare for writing the chapter on Open Access, Open Data, and other Movements towards Open for my forthcoming book Scholarly Communications for Librarians (Chandos Publishing).
The Oxford English Dictionary could really use an update on its definition of Open Access. A job for Peter Suber, perhaps?
For definitions of gratis and libre open access, see Peter Suber's article in the August 2008 SPARC Open Access Newsletter.
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