upright=0.5|thumb|class=skin-invert-image|Open access logo, originally designed by [[Public Library of Science]]
thumb|thumbtime=5:44|A [[Piled Higher and Deeper|PhD Comics introduction to open access]]
Open access (OA) is a set of principles and a range of practices through which nominally copyrightable publications are delivered to readers free of access charges or other barriers. With open access strictly defined (according to the 2001 definition), or libre open access, barriers to copying or reuse are also reduced or removed by applying an open license for copyright, which regulates post-publication uses of the work. This is because:
- such publications have been a subject of serials crisis, unlike newspapers, magazines and fiction writing. The main difference between these two groups is in demand elasticity: whereas an English literature curriculum can substitute Harry Potter and the Philosopher's Stone with a public domain alternative, such as A Voyage to Lilliput, an emergency room physician treating a patient for a life-threatening urushiol poisoning cannot substitute the most recent, but paywalled review article on this topic with a 90-year-old copyright-expired article that was published before the invention of prednisone in 1954.
- the authors of research papers are not paid in any way, so they do not suffer any monetary losses, when they switch from behind paywall to open access publishing, especially, if they use diamond open access media.
- the cost of electronic publishing, which has been the main form of distribution of journal articles since , is incommensurably smaller than the cost of on-paper publishing and distribution, which is still preferred by many readers of fiction.
Whereas non-open access journals cover publishing costs through access tolls such as subscriptions, site licenses or pay-per-view charges, open-access journals are characterised by funding models which do not require the reader to pay to read the journal's contents, relying instead on author fees or on public funding, subsidies and sponsorships. Open access can be applied to all forms of published research output, including peer-reviewed and non peer-reviewed academic journal articles, conference papers, theses, book chapters, research reports and images.
Definitions
There are different models of open access publishing and publishers may use one or more of these models.
Colour naming system
Different open access types are currently commonly described using a colour system. The most commonly recognised names are "green", "gold", and "hybrid" open access; however, several other models and alternative terms are also used.
Gold OA
In the gold OA model, the publisher makes all articles and related content available for free immediately on the journal's website. In such publications, articles are licensed for sharing and reuse via Creative Commons licenses or similar.
although this is not an intrinsic property of gold OA.
Green OA
Self-archiving by authors is permitted under green OA. Independently from publication by a publisher, the author also posts the work to a website controlled by the author, the research institution that funded or hosted the work, or to an independent central open repository, where people can download the work without paying.
Green OA is free of charge for the author. Some publishers (less than 5% and decreasing as of 2014) may charge a fee for an additional service
If the author posts the near-final version of their work after peer review by a journal, the archived version is called a "postprint". This can be the accepted manuscript as returned by the journal to the author after successful peer review.
Hybrid OA
Hybrid open-access journals contain a mixture of open access articles and closed access articles. A publisher following this model is partially funded by subscriptions, and only provide open access for those individual articles for which the authors (or research sponsor) pay a publication fee. Hybrid OA generally costs more than gold OA and can offer a lower quality of service. A particularly controversial practice in hybrid open access journals is "double dipping", where both authors and subscribers are charged. For these reasons, hybrid open access journals have been called a "Mephistophelian invention", and publishing in hybrid OA journals often do not qualify for funding under open access mandates, as libraries already pay for subscriptions thus have no financial incentive to fund open access articles in such journals.
Bronze OA
Bronze open access articles are free to read only on the publisher page, but lack a clearly identifiable license. Such articles are typically not available for reuse.
Diamond/platinum OA
Journals that publish open access without charging authors article processing charges are sometimes referred to as diamond OA. Since they do not charge either readers or authors directly, such publishers often require funding from external sources such as the sale of advertisements, academic institutions, learned societies, philanthropists or government grants. There are now over 350 platinum OA journals with impact factors over a wide variety of academic disciplines, giving most academics options for OA with no APCs. Diamond OA journals are available for most disciplines, and are usually small (<25 articles per year) and more likely to be multilingual (38%); thousands of such journals exist.
Black OA
thumb|Download rate for articles on [[Sci-Hub (black open access)]]
The growth of unauthorized digital copying by large-scale copyright infringement has enabled free access to paywalled literature. This has been done via existing social media sites (e.g. the #ICanHazPDF hashtag) as well as dedicated sites (e.g. Sci-Hub). However, the increased ease and scale from 2010 onwards have changed how many people treat subscription publications.
Gratis and libre
Similar to the free content definition, the terms 'gratis' and 'libre' were used in the Budapest Open Access Initiative definition to distinguish between free to read versus free to reuse.
Gratis open access () refers to free online access, to read, free of charge, without re-use rights. all of which require as a minimum attribution of authorship to the original authors. In 2012, the number of works under libre open access was considered to have been rapidly increasing for a few years, though most open-access mandates did not enforce any copyright license and it was difficult to publish libre gold OA in legacy journals. The biggest drawback of many Open Access licenses is a prohibition on data mining. For this reason, many big data studies of various technologies performed by economists ( as well as machine learning by computer scientists) are limited to patent analysis, since the patent documents are not subject to copyright at all.
FAIR
FAIR is an acronym for 'findable, accessible, interoperable and reusable', intended to more clearly define what is meant by the term 'open access' and make the concept easier to discuss. Initially proposed in March 2016, it has subsequently been endorsed by organisations such as the European Commission and the G20. Note, however, that FAIR principles include "A1.2: The protocol allows for an authentication and authorisation procedure where necessary." This means that a FAIR dataset may be either closed (restricted access) or open (no access restrictions). So, only FAIR data without access restrictions are open access.
Features
The emergence of open science or open research has brought to light a number of controversial and hotly-debated topics.
Scholarly publishing invokes various positions and passions. For example, authors may spend hours struggling with diverse article submission systems, often converting document formatting between a multitude of journal and conference styles, and sometimes spend months waiting for peer review results. The drawn-out and often contentious societal and technological transition to Open Access and Open Science/Open Research, particularly across North America and Europe (Latin America has already widely adopted "Acceso Abierto" since before 2000) has led to increasingly entrenched positions and much debate.
The area of (open) scholarly practices increasingly sees a role for policy-makers and research funders giving focus to issues such as career incentives, research evaluation and business models for publicly funded research. Plan S and AmeliCA (Open Knowledge for Latin America) caused a wave of debate in scholarly communication in 2019 and 2020.
Licenses
thumb|Licenses used by gold and hybrid OA journals in DOAJ
Subscription-based publishing typically requires transfer of copyright from authors to the publisher so that the latter can monetise the process via dissemination and reproduction of the work. With OA publishing, typically authors retain copyright to their work, and license its reproduction to the publisher. Retention of copyright by authors can support academic freedoms by enabling greater control of the work (e.g. for image re-use) or licensing agreements (e.g. to allow dissemination by others).
The most common licenses used in open access publishing are Creative Commons. The widely used CC BY license is one of the most permissive, only requiring attribution to be allowed to use the material (and allowing derivations and commercial use). A range of more restrictive Creative Commons licenses are also used. More rarely, some of the smaller academic journals use custom open access licenses. Some publishers (e.g. Elsevier) use "author nominal copyright" for OA articles, where the author retains copyright in name only and all rights are transferred to the publisher.
Funding
Since open access publication does not charge readers, there are many financial models used to cover costs by other means. Open access can be provided by commercial publishers, who may publish open access as well as subscription-based journals, or dedicated open-access publishers such as Public Library of Science (PLOS) and BioMed Central. Another source of funding for open access can be institutional subscribers. One example is the Subscribe to Open publishing model introduced by Annual Reviews; if the subscription revenue goal is met, the given journal's volume is published open access. The number of journals implementing this model grew from 192 in 2024 to 378 in 2025. Reactions of existing publishers to open access journal publishing have ranged from moving with enthusiasm to a new open access business model, to experiments with providing as much free or open access as possible, to active lobbying against open access proposals. There are many publishers that started up as open access-only publishers, such as PLOS, Hindawi Publishing Corporation, Frontiers in... journals, MDPI and BioMed Central.
Article processing charges
thumb|Article processing charges by gold OA journals in DOAJ The money might come from the author but more often comes from the author's [[research grant or employer. While the payments are typically incurred per article published (e.g. BMC or PLOS journals), some journals apply them per manuscript submitted (e.g. Atmospheric Chemistry and Physics until recently) or per author (e.g. PeerJ).
Charges typically range from $1,000–$3,000 ($5,380 for Nature Communications) but can be under $10, close to $5,000 or well over $10,000. APCs vary greatly depending on subject and region and are most common in scientific and medical journals (43% and 47% respectively), and lowest in arts and humanities journals (0% and 4% respectively). APCs can also depend on a journal's impact factor. Some publishers (e.g. eLife and Ubiquity Press) have released estimates of their direct and indirect costs that set their APCs. Hybrid OA generally costs more than gold OA and can offer a lower quality of service. However, there is ongoing discussion about whether the change-over offers an opportunity to become more cost-effective or promotes more equitable participation in publication. Concern has been noted that increasing subscription journal prices will be mirrored by rising APCs, creating a barrier to less financially privileged authors.
The inherent bias of the current APC-based OA publishing perpetuates this inequality through the 'Matthew effect' (the rich get richer, and the poor get poorer). The switch from pay-to-read to pay-to-publish has left essentially the same people behind, with some academics not having enough purchasing power (individually or through their institutions) for either option. Some gold OA publishers will waive all or part of the fee for authors from less developed economies. Steps are normally taken to ensure that peer reviewers do not know whether authors have requested, or been granted, fee waivers, or to ensure that every paper is approved by an independent editor with no financial stake in the journal. The main argument against requiring authors to pay a fee, is the risk to the peer review system, diminishing the overall quality of scientific journal publishing.
Subsidized or no-fee
No-fee open access journals, also known as "platinum" or "diamond" These journals use a variety of business models including subsidies, advertising, membership dues, endowments, or volunteer labour.
Estimates of prevalence vary, but approximately 10,000 journals without APC are listed in DOAJ and the Free Journal Network. APC-free journals tend to be smaller and more local-regional in scope. Some also require submitting authors to have a particular institutional affiliation. Preprint platforms have become popular due to the increasing drive towards open access publishing and can be publisher- or community-led. A range of discipline-specific or cross-domain platforms now exist. The posting of pre-prints (or authors' manuscript versions) is consistent with the Green Open Access model.
Effect of preprints on later publication
A persistent concern surrounding preprints is that work may be at risk of being plagiarised or "scooped" – meaning that the same or similar research will be published by others without proper attribution to the original source – if publicly available but not yet associated with a stamp of approval from peer reviewers and traditional journals. These concerns are often amplified as competition increases for academic jobs and funding, and perceived to be particularly problematic for early-career researchers and other higher-risk demographics within academia.
However, preprints, in fact, protect against scooping. Considering the differences between traditional peer-review based publishing models and deposition of an article on a preprint server, "scooping" is less likely for manuscripts first submitted as preprints. In a traditional publishing scenario, the time from manuscript submission to acceptance and to final publication can range from a few weeks to years, and go through several rounds of revision and resubmission before final publication. During this time, the same work will have been extensively discussed with external collaborators, presented at conferences, and been read by editors and reviewers in related areas of research. Yet, there is no official open record of that process (e.g., peer reviewers are normally anonymous, reports remain largely unpublished), and if an identical or very similar paper were to be published while the original was still under review, it would be impossible to establish provenance.
Preprints provide a time-stamp at the time of publication, which helps to establish the "priority of discovery" for scientific claims. This means that a preprint can act as proof of provenance for research ideas, data, code, models, and results. The fact that the majority of preprints come with a form of permanent identifier, usually a digital object identifier (DOI), also makes them easy to cite and track. Thus, if one were to be "scooped" without adequate acknowledgement, this would be a case of academic misconduct and plagiarism, and could be pursued as such.
There is no evidence that "scooping" of research via preprints exists, not even in communities that have broadly adopted the use of the arXiv server for sharing preprints since 1991. If the unlikely case of scooping emerges as the growth of the preprint system continues, it can be dealt with as academic malpractice. ASAPbio includes a series of hypothetical scooping scenarios as part of its preprint FAQ, finding that the overall benefits of using preprints vastly outweigh any potential issues around scooping. Indeed, the benefits of preprints, especially for early-career researchers, seem to outweigh any perceived risk: rapid sharing of academic research, open access without author-facing charges, establishing priority of discoveries, receiving wider feedback in parallel with or before peer review, and facilitating wider collaborations. which can be more restrictive and complicated than respective "gold" policies regarding deposit location, license, and embargo requirements. Some publishers require an embargo period before deposition in public repositories, arguing that immediate self-archiving risks loss of subscription income.
Embargo periods
thumb|upright|Length of embargo times for bronze [[Elsevier|Elsevier journals]] Embargoes are imposed by between 20 and 40% of journals, during which time an article is paywalled before permitting self-archiving (green OA) or releasing a free-to-read version (bronze OA). Embargo periods typically vary from 6–12 months in STEM and >12 months in humanities, arts and social sciences. and tends to increase readership and citations. Embargoes have been lifted on particular topics for either limited times or ongoing (e.g. Zika outbreaks or indigenous health). Plan S includes zero-length embargoes on self-archiving as a key principle.
- Rather than applying traditional notions of copyright to academic publications, they could be libre or "free to build upon". although others have argued that OA may raise the total cost of publication, and further increase economic incentives for exploitation in academic publishing. The open access movement is motivated by the problems of social inequality caused by restricting access to academic research, which favor large and wealthy institutions with the financial means to purchase access to many journals, as well as the economic challenges and perceived unsustainability of academic publishing.
Stakeholders and concerned communities
thumb|thumbtime=0:47|A fictional thank you note from the future to contemporary researchers for sharing their research openly
The intended audience of research articles is usually other researchers. Open access helps researchers as readers by opening up access to articles that their libraries do not subscribe to. All researchers benefit from open access as no library can afford to subscribe to every scientific journal and most can only afford a small fraction of them. This is known as the "serials crisis".
Open access extends the reach of research beyond its immediate academic circle, as an open access article can be read by anyone. A 2008 study revealed that mental health professionals are roughly twice as likely to read a relevant article if it is freely available.
Research funders
Research funding agencies and universities want to ensure that the research they fund and support in various ways has the greatest possible research impact. As a means of achieving this, research funders are beginning to expect open access to the research they support. Many of them (including all UK Research Councils) have already adopted open-access mandates, and others are on the way to do so (see ROARMAP).
Universities
A growing number of universities are providing institutional repositories in which their researchers can deposit their published articles. Some open access advocates believe that institutional repositories will play a very important role in responding to open-access mandates from funders.
In May 2005, 16 major Dutch universities cooperatively launched DAREnet, the Digital Academic Repositories, making over 47,000 research papers available. From 2 June 2008, DAREnet has been incorporated into the scholarly portal NARCIS. By 2019, NARCIS provided access to 360,000 open access publications from all Dutch universities, KNAW, NWO and a number of scientific institutes.
In 2011, a group of universities in North America formed the Coalition of Open Access Policy Institutions (COAPI). Starting with 21 institutions where the faculty had either established an open access policy or were in the process of implementing one, COAPI now has nearly 50 members. These institutions' administrators, faculty and librarians, and staff support the international work of the Coalition's awareness-raising and advocacy for open access.
In 2012, the Harvard Open Access Project released its guide to good practices for university open-access policies, focusing on rights-retention policies that allow universities to distribute faculty research without seeking permission from publishers. As of November 2023, Rights retention policies are being adopted by an increasing number of UK universities as well.
In 2013 a group of nine Australian universities formed the Australian Open Access Strategy Group (AOASG) to advocate, collaborate, raise awareness, and lead and build capacity in the open access space in Australia. In 2015, the group expanded to include all eight New Zealand universities and was renamed the Australasian Open Access Support Group. It was then renamed the Australasian Open Access Strategy Group, highlighting its emphasis on strategy. The awareness raising activities of the AOASG include presentations, workshops, blogs, and a webinar series on open access issues.
Libraries and librarians
As information professionals, librarians are often vocal and active advocates of open access. These librarians believe that open access promises to remove both the price and permission barriers that undermine library efforts to provide access to scholarship, as well as helping to address the serials crisis. Open access provides a complement to library access services such as interlibrary loan, supporting researchers' needs for immediate access to scholarship. Librarians and library associations also lead education and outreach initiatives to faculty, administrators, the library community, and the public about the benefits of open access.
Many library associations have either signed major open access declarations or created their own. For example, IFLA have produced a Statement on Open Access. The Association of Research Libraries has documented the need for increased access to scholarly information, and was a leading founder of the Scholarly Publishing and Academic Resources Coalition (SPARC). Librarians and library associations also develop and share informational resources on scholarly publishing and open access to research; the Scholarly Communications Toolkit developed by the Association of College and Research Libraries of the American Library Association is one example of this work.
At most universities, the library manages the institutional repository, which provides free access to scholarly work by the university's faculty. The Canadian Association of Research Libraries has a program to develop institutional repositories at all Canadian university libraries. An increasing number of libraries provide publishing or hosting services for open access journals, with the Library Publishing Coalition as a membership organisation.
In 2013, open access activist Aaron Swartz was posthumously awarded the American Library Association's James Madison Award for being an "outspoken advocate for public participation in government and unrestricted access to peer-reviewed scholarly articles". In March 2013, the entire editorial board and the editor-in-chief of the Journal of Library Administration resigned en masse, citing a dispute with the journal's publisher. One board member wrote of a "crisis of conscience about publishing in a journal that was not open access" after the death of Aaron Swartz.
Public
The public may benefit from open access to scholarly research for many reasons. Advocacy groups such as SPARC's Alliance for Taxpayer Access in the US argue that most scientific research is paid for by taxpayers through government grants, who have a right to access the results of what they have funded. Examples of people who might wish to read scholarly literature include individuals with medical conditions and their family members, serious hobbyists or "amateur" scholars (e.g. amateur astronomers), and high school and junior college students. Additionally, professionals in many fields, such as those doing research in private companies, start-ups, and hospitals, may not have access to publications behind paywalls, and OA publications are the only type that they can access in practice.
Even those who do not read scholarly articles benefit indirectly from open access. For example, patients benefit when their doctor and other health care professionals have access to the latest research. Advocates argue that open access speeds research progress, productivity, and knowledge translation.
Low-income countries
In developing nations, open access archiving and publishing acquires a unique importance. Scientists, health care professionals, and institutions in developing nations often do not have the capital necessary to access scholarly literature.
Many open access projects involve international collaboration. For example, the SciELO (Scientific Electronic Library Online), is a comprehensive approach to full open access journal publishing, involving a number of Latin American countries. Bioline International, a non-profit organization dedicated to helping publishers in developing countries is a collaboration of people in the UK, Canada, and Brazil; the Bioline International Software is used around the world. Research Papers in Economics (RePEc), is a collaborative effort of over 100 volunteers in 45 countries. The Public Knowledge Project in Canada developed the open-source publishing software Open Journal Systems (OJS), which is now in use around the world, for example by the African Journals Online group, and one of the most active development groups is Portuguese. This international perspective has resulted in advocacy for the development of open-source appropriate technology and the necessary open access to relevant information for sustainable development.