Co-Authorship: Who Qualifies, What It Commits You To, and How to Settle the List
Co-authorship is credit plus accountability. The four ICMJE criteria and Nature's slightly different version decide who belongs on the byline, and the list is far easier to settle before submission than after.
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Quick answer: Co-authorship means your name is on the byline, which gives you credit for the work and makes you answerable for it. Under the ICMJE Recommendations, a co-author must meet all four criteria: a substantial contribution to the design, data or analysis; drafting or critically revising the paper; approving the final version; and agreeing to be accountable for the whole work. Anyone who meets fewer than four gets an acknowledgment, not a byline slot.
Run the free readiness scan on your manuscript once the author list is settled, or use the role table below to settle it first.
Evidence basis: We read the current ICMJE page on the role of authors and contributors, the Nature Portfolio authorship policy and the PLOS ONE authorship policy on September 23, 2026. The role table and the settling procedure are our editorial synthesis of those sources. Journals outside medicine and Nature Portfolio write their own rules, so the last word is always the target journal's author instructions, and this page does not predict how any editor or institution will rule on a dispute.
The four tests, and where Nature differs
Every co-authorship question comes back to the same checklist. ICMJE asks for all four:
- A substantial contribution to the conception or design of the work, or to acquiring, analyzing or interpreting its data.
- Drafting the work or revising it critically for important intellectual content.
- Final approval of the version to be published.
- Agreement to be accountable for all aspects of the work.
Nature Portfolio adapts the same idea with three differences that change real decisions. It names the creation of new software used in the work as a qualifying contribution. It lets drafting or substantive revision stand as the contribution in its own right, where ICMJE wants a design or data contribution and drafting. And it splits accountability in two: each author answers personally for their own part and must make sure that questions about any other part are investigated and resolved.
PLOS works from the same 2018 source as Nature. It asks for a substantial contribution to design, data acquisition, analysis or interpretation, approval of the submitted version, and personal accountability for your own part, and it records each author's role with the CRediT taxonomy.
Rule | ICMJE | Nature Portfolio | PLOS ONE |
|---|---|---|---|
Must every author help draft or revise? | Yes, one of the four criteria | No, drafting is one qualifying contribution among several | No |
Co-authors contacted at submission | Not specified on the page we read | Submission is taken as everyone's agreement | Every author gets an email to confirm |
Changes after acceptance | Not specified on the page we read | Not permitted | Not generally considered |
Who settles a dispute | The authors, not the journal | The institution, not the editors | The institution; the journal will not arbitrate |
Source: ICMJE, Nature Portfolio and PLOS ONE authorship pages, read September 23, 2026.
The practical upshot: a research software engineer who wrote the analysis package can clear Nature's bar more easily than an ICMJE journal's, if they never touched the draft. Read the rule your target journal uses before you argue about a borderline name.
Co-author or acknowledgment? A role-by-role table
These are the contributions that start most authorship arguments. The verdicts assume the person did nothing else on the paper; anyone who also meets the other criteria moves up to the byline.
Contribution, on its own | Byline or acknowledgment | Why |
|---|---|---|
Secured the grant | Acknowledgment | ICMJE names acquisition of funding as not enough by itself |
Heads the lab, no hands on this paper | Acknowledgment | General supervision of a research group is on ICMJE's not-enough list |
Ran the statistics and chose the models | Byline, if they revise and approve | Analysis and interpretation of data is a qualifying contribution |
Collected samples to a written protocol | Acknowledgment under ICMJE unless they also revise; possible byline at Nature | Data acquisition qualifies at both, but ICMJE also wants drafting or critical revision |
Wrote the software the analysis depends on | Byline at Nature if they sign off; weaker case under ICMJE | Nature lists new software as a contribution |
Edited the English | Acknowledgment | Writing assistance and language editing are on ICMJE's list |
Provided a cell line or reagent | Acknowledgment | Supplying material is not design, data or analysis |
An AI tool drafted text | Neither: disclose it | ICMJE says chatbots cannot be authors |
Source: ICMJE Recommendations, Defining the Role of Authors and Contributors; Nature Portfolio authorship policy (both read September 23, 2026).
What signing on as a co-author commits you to
The byline is a promise. Before you let your name go on someone else's draft, check four things you will be held to:
- You read the version that was submitted. Nature Portfolio treats submission as meaning every listed author agreed to the contents, including the author list and the contribution statement. It does not require each author to sign the submission letter, so you may never be asked directly.
- You can answer for the paper. If a reader questions a panel you never touched, "that was the other lab" is not an answer under either rule. At minimum you have to make sure the question gets investigated.
- You agreed to your line in the contribution statement. Nature expects the author list and contributions to be certified by all authors, or by the group leaders in a multi-lab project.
- You will hear about problems after publication. Nature makes the corresponding author responsible for telling all co-authors about matters arising, which means you share the correction if one comes.
The corresponding author carries extra work. ICMJE describes the role as primary responsibility for communicating with the journal through submission, review and publication, and asks that person to be available to answer editorial queries promptly. If you are the one clicking submit, the other authors' agreement is your problem to confirm.
When the list gets locked, and how to settle it before then
Authorship fights are cheap before submission and expensive after. At Nature Portfolio journals, any change to the author list after submission (adding, deleting or reordering names) must be approved by every author, and none of those changes is permitted after acceptance. Editors there also say they are not in a position to adjudicate disputes; unresolved ones go to the relevant institution. ICMJE puts the same weight on the authors: deciding who qualifies is the authors' collective job, not the journal's.
A settling procedure that works for most labs:
- Write the contribution statement first. Draft one line per person describing what they did, in plain verbs. Names without a line are the ones to discuss.
- Run each name through the four tests for the journal you are actually targeting. Mark who fails which test, not who "deserves" credit.
- Offer the borderline contributors a path. Someone who collected data but never saw the draft can still qualify by revising critically and approving the final version. Send them the draft with a deadline.
- Move everyone else to the acknowledgments with a specific description of their help, and tell them before submission, not after they see the proof.
- Get written sign-off on the final list and order from every author before upload. An email thread is enough; silence is not.
Once the list is right, ordering the names is a separate negotiation with its own conventions.
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Where co-authorship problems show up in a submission
Across our pre-submission reviews, the author list itself is rarely what a reviewer comments on. What shows up is the paperwork around it. These are the patterns worth fixing before upload:
The missing contribution statement. Authorship credit is only as clear as the paperwork that records it. A manuscript heading to a journal that requires an author contributions section arrives without one, or with a single line saying all authors contributed equally. The $99 Submission-Ready Dossier treats an author contributions statement as a critical required element and reports whether it is present, alongside the conflict of interest, funding, ethics and data availability statements.
The statement that does not match the methods. The contribution section says one author "performed the experiments," while the methods describe work across three sites and two techniques. An editor reading both will wonder who did the imaging. Give each named method an owner.
The acknowledgment that describes an author's job. (For how to word the ones that belong there, see how to write acknowledgements for a research paper.) The acknowledgments thank someone for "designing the study and interpreting the data," which is two of the four authorship criteria. Either that person belongs on the byline or the sentence is overstating their help. Both readings are bad for you, and a reviewer who notices will start asking about guest or ghost authorship instead of your results.
The reviewer suggestion who is really a co-author. Suggested reviewers who share recent papers with the authors are a conflict editors look for. The Dossier proposes named reviewers from the OpenAlex publication graph, but it can drop the paper's own authors only when the manuscript already carries a DOI, such as a posted preprint. For an unpublished draft, check every suggested name against your author list and each author's recent coauthors before any of them goes into the submission form.
None of this is a judgment on who deserves authorship. Manusights reviews the manuscript you upload; it cannot see who did the work, and it does not rule on disputes.
Think twice before you
- add a senior name for weight. If they fail the four tests, the name adds accountability they never accepted and can surface later as a guest-authorship problem.
- leave off someone who revised the draft critically because they joined late. Timing is not one of the criteria.
- promise authorship in exchange for a reagent or dataset. Supplying material is an acknowledgment unless the provider also contributes to design, analysis or writing.
- submit before every author has seen the final version. At Nature Portfolio journals, submission itself is read as everyone's agreement.
Frequently asked questions
A co-author is one of the people named on the byline, and the name carries two things: credit for a real intellectual contribution and a share of accountability for the whole paper. Under the ICMJE Recommendations, every author must meet four criteria: a substantial contribution to the design, data or analysis; drafting or critical revision; final approval of the version to be published; and agreement to be accountable for all aspects of the work.
Not on its own. ICMJE lists acquisition of funding and general supervision of a research group as contributions that alone do not justify authorship, and asks for those people to be acknowledged instead. A lab head who also shaped the design, revised the draft critically and approved the final version does qualify.
Partly. ICMJE asks every author to agree to be accountable for all aspects of the work. Nature Portfolio frames it as personal accountability for your own contribution plus a duty to make sure questions about any other part are investigated and resolved. Either way, a co-author cannot disown a figure because another lab made it.
Usually, with conditions. At Nature Portfolio journals any change to the author list after submission must be approved by every author, and additions, deletions or reordering are not permitted after acceptance. Other publishers set their own rules, so check the target journal before the paper goes in.
No. ICMJE says chatbots such as ChatGPT should not be listed as authors because they cannot be responsible for the accuracy, integrity and originality of the work. Disclose AI use the way the target journal asks instead.
The authors. ICMJE states that it is the collective responsibility of the authors, not the journal, to determine that everyone named meets the criteria. Nature Portfolio editors say they are not in a position to adjudicate authorship disputes and send unresolved ones to the relevant institution.
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