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?
- Which funders require preprinting in 2026?
- How does the NIH Preprint Pilot treat bioRxiv deposits?
- Does Wellcome require or just encourage preprints?
- What changed when bioRxiv and medRxiv became openRxiv?
- Common questions about bioRxiv and preprint servers
- What this means for institutions and researchers
- The direction of travel for funder preprint policy
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.