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Medium defines plagiarism as any act of taking the words and/or ideas of others and presenting them as original or without proper acknowledgement or permission. This includes directly copying ideas and text (whether entire articles, paragraphs, or sentences), as well as paraphrasing and slight re-writes (often known as "mosaic plagiarism"), and failure to cite sources.
Medium requires that the sources of quoted or paraphrased content potentially included under Fair Use be properly cited within posts. Proper citations of sources in any of the major systems of citations are welcome, and can be added using numbered superscript text formatting, or other appropriate methods.
Detected instances of plagiarism on Medium may result in suspension of posts or accounts, and having Partner Program payments withheld.
Medium deals with claims of copyright violation in accordance with the DMCA. To submit a DMCA claim, you must be the rights holder, or their authorized representative. Our DMCA & Copyright Policy contains additional information on filing a claim.
While Medium is not able to provide specific legal advice on this matter, we recommend reading the EFF's article on Fair Use.