CASRAI Dictionary

Tag: biorxiv preprint

  • bioRxiv Microbiology: 2026 Subject Growth

    bioRxiv’s microbiology collection holds more than 41,000 preprints as of July 2026, making it the platform’s third-largest subject area behind neuroscience (over 90,000) and bioinformatics (nearly 43,000). Together, these three fields account for close to two-fifths of every preprint ever posted to bioRxiv since its 2013 launch — a concentration that says as much about where biology’s fastest-moving fields are as it does about the platform itself.

    bioRxiv is a free, non-profit preprint repository for the biological sciences, now operated by openRxiv, on which authors post manuscripts before or independent of journal peer review, sorted into 27 subject-specific collections spanning everything from paleontology to synthetic biology.

    What is bioRxiv, and how are preprints organised by subject?

    bioRxiv was co-founded by John Inglis and Richard Sever in November 2013 as an open-access preprint repository hosted by Cold Spring Harbor Laboratory. In March 2025, bioRxiv and its clinical-sciences counterpart medRxiv transferred to openRxiv, a newly formed non-profit created specifically to steward both platforms, as reported by Science.

    Every submission is placed into one of 27 subject collections at the point of posting. There is no fee to submit to bioRxiv, and authors self-select the collection that best matches their manuscript. This subject taxonomy is what makes volume comparisons across fields possible — and what this analysis draws on directly.

    One structural exception worth noting: the Epidemiology collection is now closed to new submissions following the completion of bioRxiv’s clinical-research pilot project, meaning its growth curve has effectively flattened while other collections continue to expand.

    How does bioRxiv microbiology compare to neuroscience and other subjects by volume?

    Based on a live count of bioRxiv’s own subject-collection pages taken on 3 July 2026, neuroscience is the platform’s largest single collection at 90,290 preprints — a 19.4% share of the roughly 465,700 preprints posted across all 27 collections to date. Bioinformatics follows at 42,825 (9.2%), with microbiology close behind at 41,133 (8.8%).

    Cell biology, evolutionary biology, genomics and biophysics round out the next tier, each holding between roughly 21,000 and 26,000 preprints. At the other end of the scale, paleontology (678) and clinical trials (138) remain niche collections by comparison, while epidemiology’s 2,067 total is now largely fixed given its closure to new submissions.

    Full ranking of bioRxiv’s largest subject collections

    Rank Subject collection Cumulative preprints Share of total
    1 Neuroscience 90,290 19.4%
    2 Bioinformatics 42,825 9.2%
    3 Microbiology 41,133 8.8%
    4 Cell Biology 25,753 5.5%
    5 Evolutionary Biology 24,737 5.3%
    6 Genomics 22,868 4.9%
    7 Biophysics 21,837 4.7%
    8 Ecology 20,284 4.4%
    9 Cancer Biology 18,775 4.0%
    10 Biochemistry 18,098 3.9%

    Source: CASRAI analysis of live bioRxiv subject-collection article counts, recorded 3 July 2026. These are cumulative totals since bioRxiv’s 2013 launch, not annual submission rates, so they reflect sustained field-level adoption of preprinting rather than a single year’s activity.

    Microbiology’s position just behind bioinformatics is notable given how differently the two fields work: bioinformatics preprints are often fast, computational and low-cost to produce, while microbiology preprints typically follow wet-lab experimental cycles. That microbiology has nonetheless built a corpus within a few thousand papers of bioinformatics points to strong, sustained preprinting culture within microbiology specifically — likely reinforced by the field’s pandemic-era experience with rapid-dissemination norms.

    Why does subject-level concentration matter for research administrators?

    For institutional leaders and research-administration teams, subject-level preprint concentration is a proxy for where scholarly communication norms are shifting fastest. A field with tens of thousands of preprints has, in effect, normalised pre-peer-review dissemination as a routine step in its publication workflow — with direct implications for how institutions track outputs, credit early dissemination in tenure and promotion review, and advise researchers on preprint policy.

    • Grant and promotion committees increasingly need clear policy on whether preprints count as citable outputs, particularly in high-volume fields like neuroscience and microbiology.
    • Research offices supporting microbiology, bioinformatics or genomics groups should expect preprint-first workflows to already be the norm, not the exception, among active researchers.
    • Fields with low preprint volume (pathology, zoology, clinical trials) may need different guidance, since preprinting culture there remains comparatively immature.

    This is also a live concern for research administrators and institutional leaders tracking how open-research norms diffuse unevenly across disciplines — subject-level data of this kind gives institutions a concrete basis for that assessment, rather than relying on anecdote.

    Common questions about bioRxiv preprints

    Is bioRxiv a preprint server?

    Yes. bioRxiv is a dedicated preprint server for the biological sciences, distributing manuscripts before or alongside formal peer review. It is operated by openRxiv, a non-profit created in 2025 specifically to run bioRxiv and medRxiv, and hosts subject collections spanning microbiology, neuroscience, genomics and 24 other biology-related fields.

    Can anyone submit to bioRxiv?

    Authors can deposit a manuscript in draft or final form provided it concerns a relevant scientific field, is unpublished at the time of submission, and all co-authors have consented. Authors must first register on the platform. bioRxiv screens submissions for basic scope and ethical compliance before posting, but does not conduct peer review.

    How much does it cost to publish in bioRxiv?

    There is no fee to submit a preprint to bioRxiv. This free-to-post model is a key driver of its growth across every subject collection, including the microbiology and neuroscience volumes analysed above, since it removes the cost barrier that applies to many open-access journal publication routes.

    Does bioRxiv count as published?

    A bioRxiv preprint is not equivalent to a peer-reviewed publication. It establishes a timestamped, citable public record of the work, and many journals allow later submission of the same manuscript, but it has not undergone formal peer review at the point of posting. Institutions and funders vary in how they weight preprints in assessment.

    Implications and outlook for scholarly communication

    The concentration of preprint volume in neuroscience, bioinformatics and microbiology is likely to persist rather than reverse. These fields combine large, active researcher populations with production cycles well suited to rapid dissemination, and none shows structural barriers comparable to epidemiology’s now-closed pilot pathway.

    For research-administration teams, the practical takeaway is to treat preprint-volume data by subject as a planning input: policy on preprint citation, researcher guidance, and repository integration should be calibrated to each discipline’s actual adoption level rather than applied uniformly across an institution’s full research portfolio.

  • Chai-2 bioRxiv: Comparing AI Biology Preprints Ahead of Peer Review

    The Chai-2 bioRxiv preprint, posted by Chai Discovery on 5 July 2025, reports a 16% hit rate in fully de novo antibody design — more than 100-fold above prior computational methods — but like the ESM3 and Geneformer foundation models it sits alongside, the claim has not yet cleared peer review. All three are part of a wider pattern: AI biology foundation models are increasingly disseminated as bioRxiv preprints first, journal articles later (if at all), which changes how institutions, publishers, and funders must scrutinise their claims.

    A bioRxiv preprint is a manuscript posted to the Cold Spring Harbor Laboratory’s biology preprint server before, or instead of, formal peer review. This article compares how Chai-2, ESM3, Geneformer, EvolvePro, and AlphaFold-Multimer have each used that route, and what the differences mean for reproducibility.

    What is Chai-2, and why was it posted as a bioRxiv preprint?

    Chai-2 is a multimodal generative model from Chai Discovery that designs antibodies and nanobodies from scratch, taking a target structure and epitope as input and returning a complete antibody design. The original preprint, “Zero-shot antibody design in a 24-well plate”, reported a 16% success rate in de novo design against 52 diverse targets, completed from AI design to wet-lab validation in under two weeks.

    Chai Discovery followed with an updated bioRxiv preprint on 29 November 2025, “Drug-like antibody design against challenging targets”, reporting that more than 86% of designed full-length monoclonal antibodies showed developability profiles comparable to approved therapeutics. Neither preprint has yet been published in a peer-reviewed journal. The company has since raised a $130 million Series B round, taking total funding above $225 million at a $1.3 billion valuation, according to Genetic Engineering & Biotechnology News.

    How do ESM3 and Geneformer differ from Chai-2 in preprint dissemination?

    ESM3 and Geneformer address different biological scales entirely, and their publication paths diverge from Chai-2’s in an instructive way. ESM3, from EvolutionaryScale, is a general-purpose protein language model trained on roughly 2.78 billion protein sequences with a 98-billion-parameter flagship configuration. It was posted as a preprint before its 2025 publication in Science — meaning it eventually completed the peer-review cycle that Chai-2’s antibody preprints have not yet reached.

    Geneformer operates at the cellular level rather than the molecular level. Built on a transformer-encoder architecture pretrained across tens of millions of single-cell RNA-sequencing profiles, it classifies cell types and predicts disease-relevant genes. Its foundational description, credited to Christina Theodoris and colleagues, circulated as a preprint before formal publication in Nature in 2023.

    EvolvePro and AlphaFold-Multimer extend the comparison further. EvolvePro is a few-shot protein-engineering framework that uses language-model embeddings to guide directed evolution from very few labelled variants, disseminated via bioRxiv. AlphaFold-Multimer, Google DeepMind’s extension of AlphaFold2 for multi-chain complex prediction, is the starkest case: its 2021 bioRxiv preprint (Evans et al.) has been cited thousands of times and underpins structural biology workflows worldwide, yet it has never been published in a peer-reviewed journal.

    Model Domain bioRxiv posting Weight access Peer-review status
    Chai-2 De novo antibody design v1 Jul 2025; updated Nov 2025 Platform/API access, not fully open weights Preprint only
    ESM3 General protein sequence/structure/function Preprint, then Science (2025) Smaller checkpoints open; 98B flagship gated via Forge API Peer-reviewed
    Geneformer Single-cell transcriptomics Preprint, then Nature (2023) Fully open-weight release Peer-reviewed
    EvolvePro Few-shot directed protein evolution bioRxiv preprint Open code/model release Preprint at time of posting
    AlphaFold-Multimer Multi-chain complex structure prediction bioRxiv preprint (2021) Code and weights open-sourced Never published in a peer-reviewed journal

    Why does preprint-first publication intensify reproducibility scrutiny?

    Preprint-first publication compresses the interval between a headline result and its public citation, which is valuable for fast-moving fields but removes a layer of independent verification before claims circulate. AlphaFold-Multimer shows this can persist indefinitely: a preprint can become de facto infrastructure without ever completing formal review.

    • Model weight access varies sharply: Geneformer and AlphaFold-Multimer are fully open, while Chai-2 and ESM3’s largest configuration require platform or API access, limiting independent replication of the exact reported result.
    • Benchmark scale differs: Chai-2’s 16% hit rate is drawn from a company-run benchmark across 52 targets, not an externally adjudicated challenge such as CASP or CAPRI.
    • Versioning matters: Chai-2’s updated November 2025 preprint extends claims to full-length monoclonal antibodies, meaning readers must track which version underlies any given statistic.

    For research administrators and institutional evaluators, the practical implication is that a citation to “Chai-2” or “ESM3” is not self-evidently a citation to peer-reviewed work — the preprint status, version, and weight-access terms all need checking before the claim is treated as settled.

    Common questions about AI biology preprints on bioRxiv

    Is the Chai-2 bioRxiv preprint peer-reviewed?

    No. As of publication, both Chai-2 preprints — the July 2025 original and the November 2025 update — remain bioRxiv preprints. Neither has completed formal peer review, so the reported 16% hit rate and 86% developability figures should be read as company-reported, not journal-vetted, results.

    Has ESM3 been published in a peer-reviewed journal?

    Yes. ESM3 was first circulated as a preprint before EvolutionaryScale’s results were published in Science in 2025, giving it a completed peer-review path that Chai-2’s antibody-design claims currently lack.

    What is Geneformer used for?

    Geneformer analyses single-cell RNA-sequencing data to classify cell types, model gene regulatory networks, and identify disease-relevant genes, using a transformer architecture trained on large single-cell transcriptome corpora rather than protein or antibody sequences.

    What is the difference between Chai-2 and AlphaFold-Multimer?

    AlphaFold-Multimer predicts the 3D structure of existing multi-chain protein complexes, while Chai-2 generates entirely new antibody sequences and structures for a chosen target — structure prediction versus de novo generative design.

    What are the implications for institutions, publishers, and funders?

    Research administrators citing Chai-2, ESM3, Geneformer, or comparable models in grant reports, technology assessments, or institutional communications should distinguish preprint claims from peer-reviewed findings explicitly, note the exact preprint version, and record whether model weights are open or platform-gated. Publishers and editors evaluating manuscripts that build on these models should likewise verify which version of the underlying preprint is cited, since headline metrics can shift between versions.

    The broader lesson is structural rather than model-specific: as AI biology moves faster than journal review cycles, the preprint-to-journal gap itself becomes a due-diligence checkpoint that institutions, funders, and publishers now need to track as routinely as they track the results themselves.

  • BioRxiv Preprint Server: NIH, Wellcome and Gates Compared

    Funder preprint requirements diverge sharply in 2026: the Gates Foundation and the Howard Hughes Medical Institute (HHMI) now mandate deposit on a recognised server such as the preprint server bioRxiv or its sister site medRxiv, the NIH indexes eligible preprints in PubMed Central without treating them as compliance, and Wellcome requires them only in defined public-health-emergency scenarios. Research administrators tracking multi-funder portfolios need a single reference for which rule applies where.

    A preprint server is an open-access repository — such as bioRxiv for biology or medRxiv for health sciences — where researchers post a complete but not-yet-peer-reviewed manuscript for immediate public access. Both platforms are operated by openRxiv, a nonprofit formed in 2025 specifically to run bioRxiv and medRxiv independently of their founding host institution.

    What Is a Preprint Server Like bioRxiv?

    A preprint server is a repository for manuscripts that have not yet completed formal peer review. bioRxiv, co-founded by John Inglis and Richard Sever, launched in November 2013 as a life-sciences equivalent to arXiv. Its companion site, medRxiv, covers health and clinical research and applies additional pre-posting screening because of the sensitivity of medical findings.

    Submissions to both platforms undergo basic scrutiny — plagiarism screening, an appropriateness check, and a safeguarding review — but not peer review itself. Roughly two-thirds of bioRxiv preprints are later published in a peer-reviewed journal, and by early 2026 bioRxiv was recording around four million article downloads a month, according to a Nature analysis of the server’s first 13 years.

    Which Funders Require Preprinting in 2026?

    Funder policy on preprints splits into three tiers: outright mandates, conditional requirements, and pure encouragement. The table below summarises the position of four major research funders as of 2026.

    Funder Preprint requirement Effective date Compliance role
    Gates Foundation Mandatory — deposit before or at journal submission, CC BY licence 1 January 2025 Core requirement of the Open Access Policy
    HHMI Mandatory for HHMI investigators, scholars and Janelia scientists 1 January 2026 Preprint required before journal submission
    Wellcome Trust Required only for research with significant public health implications; encouraged otherwise Ongoing Accepted as a fallback open access route if a fully OA journal or Europe PMC deposit is unavailable
    NIH Not required Preprint Pilot ongoing Discoverability only — does not satisfy the NIH Public Access Policy

    Two funders — Gates and HHMI — now treat preprinting as a compulsory step in the research lifecycle. NIH and Wellcome instead fold preprints into a wider menu of open access routes, which is the detail most other coverage of this topic omits.

    How Does the NIH Preprint Pilot Treat bioRxiv Deposits?

    The NIH Preprint Pilot makes eligible NIH-funded preprints — including bioRxiv and medRxiv deposits — discoverable in PubMed Central and PubMed, tagged clearly as preprints rather than peer-reviewed literature. This is a discoverability mechanism, not a compliance mechanism.

    Posting a preprint does not fulfil the NIH Public Access Policy. Grantees must still deposit the final, accepted peer-reviewed manuscript in PMC. NIH does, however, permit researchers to cite preprints in grant applications and progress reports, which gives early findings some formal standing without changing the underlying compliance obligation.

    Does Wellcome Require or Just Encourage Preprints?

    Wellcome strongly encourages preprinting across its funded portfolio and requires it specifically where a disease outbreak or comparable public health emergency makes rapid sharing a priority. Outside those defined scenarios, preprinting is not compulsory.

    Wellcome’s primary open access compliance routes are publication in a fully open access journal or deposit of the author’s accepted manuscript in Europe PMC. A CC BY-licensed preprint is accepted as a valid compliance route only if neither of those primary routes is available — a fallback position, not a default requirement.

    What Changed When bioRxiv and medRxiv Became openRxiv?

    bioRxiv and medRxiv were hosted by Cold Spring Harbor Laboratory (CSHL) from launch until 11 March 2025, when ownership transferred to openRxiv, a newly formed nonprofit dedicated solely to running the two preprint servers. This is a provenance detail funder-policy roundups routinely miss, and it matters for research administrators: openRxiv, not CSHL, is now the governing body whose terms of use and licensing options apply to deposits made under Gates, HHMI, Wellcome and NIH-linked research.

    The Chan Zuckerberg Initiative has funded platform development on both sites since 2017, part of a broader pattern of philanthropic infrastructure investment that runs parallel to — and distinct from — the funder mandates covered above.

    Common Questions About bioRxiv and Preprint Servers

    Is bioRxiv a preprint server?

    Yes. bioRxiv is an open-access preprint server for the biological sciences, hosting complete but not-yet-peer-reviewed manuscripts. It does not conduct peer review itself, though submissions undergo basic screening and reviews from journals or platforms such as Review Commons may be posted alongside preprints.

    Is it free to publish on bioRxiv?

    Yes. Authors register without charge and there is no fee to deposit a manuscript on bioRxiv or medRxiv. This zero-cost deposit model is one reason funders increasingly treat preprinting as a low-friction first step toward full open access compliance.

    What is a preprint server?

    A preprint server is an online repository where researchers post manuscripts before or during formal peer review, giving the wider research community immediate access to findings. bioRxiv and medRxiv are the leading discipline-specific examples in the life and health sciences.

    What are the disadvantages of preprints?

    Preprints add an extra step to the publishing process, are not peer-reviewed at the point of posting, and can attract premature media coverage or public comment before findings are validated. Some journals and funders still weigh these risks against the benefit of faster dissemination.

    What This Means for Institutions and Researchers

    Research administrators managing grants across multiple funders now need to track preprint policy at the individual-funder level rather than assuming a single institutional rule applies. A grantee funded jointly by Gates and NIH, for example, must preprint to satisfy Gates while still separately depositing the accepted manuscript in PMC for NIH.

    • Confirm licence requirements before deposit — Gates and HHMI specify CC BY, which is not the default licence offered on every server.
    • Do not treat NIH Preprint Pilot indexing as equivalent to Public Access Policy compliance — the two are separate obligations.
    • Check Wellcome’s public-health-emergency criteria before assuming preprinting is optional on a given grant.
    • Record the openRxiv terms of use in grant files, since bioRxiv and medRxiv are no longer governed by Cold Spring Harbor Laboratory.

    The Direction of Travel for Funder Preprint Policy

    The trend across 2025 and 2026 runs firmly toward mandatory preprinting among the largest philanthropic funders, while NIH and Wellcome hold a more conditional position rooted in their existing open access frameworks. Institutions should expect more funders to follow the Gates and HHMI model as preprint infrastructure matures under openRxiv’s independent stewardship. Research administration teams that build funder-specific preprint checklists now, rather than applying a single blanket policy, will be better placed as more mandates convert from encouragement to requirement.

    For related definitions and terminology used across research administration and open access compliance, see the CASRAI Dictionary and the research administration resource hub.

  • Is bioRxiv Peer-Reviewed? What Screening Checks

    bioRxiv preprints are not peer-reviewed. Every submission passes a basic screening process — checked for plagiarism, offensive or non-scientific content, and research-integrity or biosecurity concerns — before posting, usually within 24-48 hours. That screening confirms a manuscript is a genuine, appropriately scoped scientific report; it does not evaluate whether the methods are sound, the data support the conclusions, or the findings are correct. Formal peer review only happens later, if and when the manuscript is submitted to a journal or an independent review service.

    bioRxiv is a free preprint server for the life sciences, operated by the non-profit openRxiv and founded by Cold Spring Harbor Laboratory in 2013, that lets researchers post manuscripts publicly before or during journal submission.

    What bioRxiv’s screening process actually checks

    bioRxiv runs a documented two-step screen on every submission. The first pass is done by in-house staff with scientific and editorial backgrounds, who confirm the manuscript is complete, correctly formatted, and within the server’s life-sciences scope. This stage automatically checks for plagiarism and rules out content that is not a research article — news items, advertisements, policy statements, narrative reviews, and protocols without new data are all excluded.

    The second pass is carried out by bioRxiv Affiliates, a network of volunteer principal investigators, who confirm the work is genuine biological research and flag anything that could pose a public-health or biosecurity risk, including what the US National Institutes of Health defines as dual-use research of concern. Overtly identifying patient information is also removed at this stage.

    • Plagiarism detection against published and preprint literature
    • Confirmation the submission is a scientific research article, not opinion, protocol, or promotional content
    • Dual-use and public-health risk screening by volunteer affiliates
    • Removal of overt patient- or participant-identifying material
    • Scope check — routing clinical-research submissions to medRxiv where appropriate

    bioRxiv’s own documentation states that roughly 5% of submissions do not clear this screen and are not posted. Screening typically completes within 24-48 hours — a fraction of the weeks or months a journal’s peer review takes, which is the entire point of a preprint server.

    Screening vs peer review: what’s the difference

    Screening is a gatekeeping check on form and conduct. Peer review is an expert evaluation of scientific substance — whether the experimental design supports the stated conclusions, whether statistics are applied correctly, and whether the work advances the field. bioRxiv is explicit that no endorsement of an article’s methods, assumptions, conclusions, or scientific quality is implied by its appearance on the server.

    Dimension bioRxiv screening Formal peer review
    Who performs it In-house staff + volunteer affiliates Independent subject-matter expert reviewers
    What it checks Plagiarism, scope, ethics, biosecurity, format Methodology, data integrity, validity of conclusions
    Typical duration 24-48 hours Weeks to several months
    Outcome Posted or rejected (~5% rejected) Accept, revise, or reject a specific journal submission
    Result on the record A citable preprint with a DOI A certified, published journal article

    Some preprints do receive structured external review while still hosted as preprints — eLife launched its Preprint Review service on bioRxiv in May 2020, and services such as Review Commons operate similarly. These are useful signals, but they are separate, named services layered on top of bioRxiv, not a function of bioRxiv’s own screening.

    Independent research (Abdill & Blekhman, cited widely including on Wikipedia) has found that roughly two-thirds of bioRxiv preprints are eventually published in a peer-reviewed journal, and bioRxiv automatically links to the published version once a match is found. That figure is a useful proxy for eventual quality, but it says nothing about the third that are never formally reviewed, and it cannot be applied to any single preprint you are reading today.

    Is medRxiv peer-reviewed too?

    No. medRxiv, bioRxiv’s sister server for clinical and health-related research, follows the same principle: manuscripts are screened, not peer-reviewed. Because medRxiv covers clinical and public-health topics, its screening is deliberately stricter — submissions undergo additional review for content that could directly influence patient behaviour or clinical practice, and certain categories (such as case reports without a clear scientific contribution) are restricted or excluded outright.

    The same “originator, not owner” caution applies here as everywhere in preprint literature: a medRxiv posting is not evidence of clinical validation and should not be treated as equivalent to a peer-reviewed clinical trial report or a regulatory submission.

    What happens to a preprint after it’s screened and posted

    Once posted, a bioRxiv preprint is permanent and citable. It receives a DOI immediately, cannot be withdrawn once published, and authors can post revised versions that retain the same DOI. Authors typically submit the same manuscript to a journal in parallel or afterwards, where it then enters that journal’s own peer-review process.

    bioRxiv operates a “bioRxiv-to-journal” (B2J) transfer service with more than 300 partner journals — including Cell Reports, PLOS Biology, Genetics in Medicine, and Molecular Biology of the Cell — allowing authors to send a screened preprint directly into a journal’s submission and peer-review pipeline without re-uploading files. This accelerates the path from preprint to certified publication but does not shortcut peer review itself.

    • Readers can post public comments, moderated to professional standards
    • bioRxiv reserves the right to remove plagiarised material or work found to breach research-integrity standards after posting
    • A link to the eventual published version is added automatically, usually within a few weeks of journal publication

    Common questions about bioRxiv and peer review

    Is bioRxiv credible?

    bioRxiv is a credible, widely used distribution channel run by a respected non-profit, but credibility of the platform is separate from validity of any individual manuscript. Screening filters out plagiarism and ethical breaches; it does not certify scientific quality, so each preprint must be read critically on its own merits.

    Is it okay to cite bioRxiv?

    Yes — bioRxiv preprints receive a DOI and are formally citable as part of the scientific record. Most style guides and journals require the citation to note explicitly that the source is an unrefereed preprint, so readers understand it has not passed formal peer review.

    Is a preprint a reliable source?

    A preprint can be a reliable indicator of ongoing research but is not a validated source in the way a peer-reviewed article is. Reliability depends on the specific manuscript — its methods, transparency, and any subsequent independent review — not on the preprint server’s basic screening alone.

    Is bioRxiv considered published?

    bioRxiv preprints are publicly posted and citable, but they are not “published” in the traditional peer-reviewed sense used by journals, funders, and most academic assessment exercises. Many institutions and funders explicitly distinguish preprints from peer-reviewed publications in reporting requirements.

    Implications for authors, readers, and institutions

    For authors, bioRxiv’s fast, lightly gated screening is the trade-off that makes rapid dissemination possible — but it also means responsibility for accuracy sits with the authors, not the platform, until formal peer review occurs. For readers and journalists, the practical rule is definitive: treat unreviewed bioRxiv claims as provisional, check whether a published, peer-reviewed version exists via the automatic journal link, and note preprint status explicitly whenever citing or reporting on one. For institutions building research-integrity or preprint-citation policies, bioRxiv’s own screening criteria — plagiarism, scope, dual-use risk, and patient confidentiality — are a useful documented baseline to reference, precisely because they are narrow and clearly bounded rather than a substitute for peer review.

    As preprint volume continues to grow across the life sciences, the distinction between “screened” and “peer-reviewed” is likely to matter more, not less — particularly as overlay review services like eLife’s Preprint Review and Review Commons expand the space between the two.