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Case discussion: Suspected plagiarism

Case 19-04 Suspected plagiarism

A single author submitted a paper to a journal. A similarity check revealed 48% similarity with another published paper. The published paper was by different authors—5 in total. The similarities between the papers were in the introduction, methods and discussion sections. The submitting author did not reference the published article.

We queried the corresponding author but have not received a response. 

Question(s) for the COPE Forum
• What shall we do given this circumstance? 
• Should we withdraw/reject the article and embargo the author?
• Should we contact the author’s institute without receiving any clarifications from the author?
• How long should we wait for a response from the author before reporting to the institute?



This case is categorised as a violation of Intellectual Property (IP) standards, which is a core practice that journals must address in their policies and procedures. COPE states: “All policies on intellectual property, including copyright and publishing licenses, should be clearly described. In addition, any costs associated with publishing should be obvious to authors and readers. Policies should be clear on what counts as prepublication that will preclude consideration. What constitutes plagiarism and redundant/overlapping publication should be specified.”

Issues around plagiarism often include both ethical considerations (misappropriation of another’s work, undisclosed reuse of content) and legal considerations (violation of another’s copyright or other proprietary right).  With respect to ethical considerations, often the editor’s actions may be guided by questions of intent.

In this case, the original paper was published by other authors, not including the author described in the case, and there was no citation to the original paper from which the overlapping text was used. It appears the editor was unsure if the overlap was unintentional (e.g., the author using another’s text as a template for proper language expression), or if the offending author had intentionally used another’s methods and discussion (IP) to generate an easy publication. Every experienced editor knows that some new authors are confused by the publication process and are not mentored properly on how to write for publication, so if the editor suspects that the author’s plagiarism may have arisen from a lack of knowledge or understanding, it is common for an editor to prefer educational remedies over reporting to an institution.

Conversely, where the editor feels the author acted with an improper intent, it is worth remembering that the institutions where the authors work have much better access to conduct an appropriate investigation. In cases involving funding from the U. S. government, the U.S. Office of Research Integrity (ORI) classifies serious plagiarism as misconduct and represents another option through which editors can refer a case for investigation. In such cases, an editor may choose not to advise the author of his/her decision to contact an institution and request an investigation, as this forewarning might give the authors time to remove incriminating evidence from their computers.

Of course, there is no easy way for editors to ascribe motive to an author. All the editor can do is ask for an explanation from the author and refer the case to the institution oversight committee if the response is unsatisfactory.

With respect to legal considerations, the author’s intent is largely immaterial to the question of whether a copyright violation has occurred. To minimise the risk of an intentional or unintentional IP infringement, guidelines on protection of other IP in a manuscript should be clearly stated by the journal and publisher.  This includes not only what constitutes an IP violation but also what the journal/publisher’s response and recourse might be. Agreement by the submitting author(s) to having met those guidelines should be acknowledged at the time of submission. With respect to plagiarism and reuse of materials, author guidelines must have clear instructions on obtaining acceptable permissions to use previously copyrighted material in a paper. To re-publish a figure, a copyrighted survey tool or patented methodology in a new manuscript, the author needs to know who holds the IP to the original work and the scope of the permission needed, the latter of which may depend upon the publishing plan (e.g., use in on-line or print media, potential circulation, translations). Costs of obtaining permissions are usually borne by the author requesting permission and not the journal.

Procedures such as these are an important part of Journal Management, another core practice. Failure to protect IP can subject the journal or publisher to potentially costly litigation and payment of damages or royalties to the aggrieved IP owner. In addition to detailed guidelines, there should be flags or checks in the submission and publication systems to prompt the author to upload needed permissions. The original holders of the copyright should also approve the credit line to accompany a reprinted figure. Protection of other types of IP (e.g., patented materials or methods) should be safeguarded with policies allowing authors to retain copyright to necessary information while still allowing publication of the manuscript. Authors should be advised of what rights they retain when transferring copyright to a journal.


Regardless of intent, a nearly 50% match to a single previously published paper constitutes plagiarism, and the Forum agreed that the editor must act. The Forum advised contacting the author one more time, and specifically stating that if no response is received within a given time frame, then the editor will contact the author’s institution and ask them to investigate. The editor should be very clear about the date by which a response is expected—this may provide motivation for the author to respond. If the author fails to respond, then the editor should contact the institution. The Forum did not agree that withdrawing or rejecting the manuscript or banning the author were acceptable actions. COPE does not normally advise banning authors because of legal implications and other concerns.

The Forum asked what is the percentage similarity that should raise concerns? This varies widely—by discipline, even by editors within the same discipline. The similarity index needs to be reviewed carefully, and experienced editors will look at all aspects of the article and the sources when deciding if there is significant overlap. Is there a minimum cut-off score below which there is no need to check for plagiarism? One study found a cut-off value of 15% to be useful. Well trained editorial and publishing staff could monitor trends in submissions for specific journals to make a good guideline for efficient plagiarism checking.

If the editor believes that there was no malicious intent on the part of the authors, an educational approach may be appropriate (e.g., junior researchers, students, first-time authors). The editors could explain what is expected of authors in terms of attribution of text, and best practice in this area. However, the editor may not be in a position to know the intent of the authors and this would be better addressed by the institution. Another core practice that applies here is Complaints and Appeals: Journals should have a clearly described process for handling complaints against the journal, its staff, editorial board, or publisher. A statement to the author in a letter might include information on how to appeal the decision if the author believes the accusation of plagiarism is unfair.

The journal cannot proceed moving this article forward until some of these questions are answered. Failure to follow through on possible significant plagiarism by simply rejecting the manuscript leaves the author free to submit elsewhere. Copyright is a legal issue and editors and publishers have to take their responsibilities to protect the IP of all authors seriously.

COPE Past Secretary Charon Pierson, COPE Council Timothy Devinney, COPE Secretary Tara Hoke

Read May 2019 Digest newsletter for the first letter from our new Chair, Deborah Poff, answers to questions taken at our Allegations of Misconduct webinar, and updated guidance "Ethical Editing For New Editors". We have the key findings from our research to further understand the issues faced by editors in the arts, humanities and social science which is in an easy to browse format. Charon Pierson reflects on our North American seminar "Issues of inclusivity and diversity in scholarly publishing in the arts humanities, and social sciences", with links to key resources and presentations from the speakers. Plus the monthly news and events roundup.