Open Access publications provide immediate (where applicable), unrestricted, online access to scholarly, peer-reviewed articles. Gratis OA removes price barriers alone, and Libre OA removes price barriers and at least some permission barriers as well. Under the OA model authors are free of most copyright restrictions and may freely reuse and disseminate their work.
- Gold OA
- The final publisher version is open access via the journal website without any embargo period.
- The publication has a license intended to maximize reuse, such as CC-BY.
- The author(s) may be subject to paid an additional article processing charge (APC) by the publisher.
- Green OA
- Authors can archive their paper in an full-text journal or subject repository or in their institutional repository.
- The version archived is usually the final author version as accepted for publication.
- There are no additional charges to paid.
- Publisher embargo period may apply (usually 12 months).
- Delayed OA
- Scholarly articles in subscription-based journals made openly accessible at the expiry of a set embargo period. See also: NIH Pubic Access Pollicy LibGuide.
- Hybrid OA
- Publishers offer a combination of subscription-based and open access.
- Authors may pay a fee to ensure their paper is open and can be access immediately.
- Diamond OA
- Similar to Gold OA.
- Authors are not required to pay article processing charges (APCs).
The “HowOpenIsIt?®” was created by SPARC in conjunction with PLOS, and the Open Access Scholarly Publishers Association (OASPA) as a guide that standardizes Open Access terminology in an easily understandable, comprehensive resource.