How to remove a co-author from an article published on arXiv?

Question

I have published an article on arXiv. I associated person X as co-author whereas he didn't contribute at any step of the paper. Note that he is not registered as owner of the article on arXiv and I didn't give him the password to access as author.

When I wanted to submit the paper to a journal, X began to do some harassment. After that, I decided to remove his name from the article on arXiv.

Questions: How can I remove a co-author from an article published on arXiv? Can he claim that he is the co-author on arXiv or for a journal submission?

Answer 1

Yes, technically one can modify the authors of an arXiv article. See the replace instructions on arXiv. See also this answer on Quora. But, as far as I understand these instructions, the previous version with the initial co-authors will remain on the server.

Note that it was no good scientific practice to initially associate a co-author to the paper that didn't contribute to it. Regaring the claiming of the authorship by X after removing his name from the paper, I have no answer.

Answer 2

It is not possible to change the authors of the version you already submitted to the arXiv. You can update the arXiv paper, and in the process make changes to the author list. The original author list remains accessible however.

If you do this, submit the article to some journal without X as coauthor, and X complains to the journal claiming authorship, the situation looks as follows: The journal can verify that you at some point claimed that X were a coauthor of the paper, and that you are now claiming that he is not. Thus, it is obvious that you lied at some point, serverly damaging your credibility and demonstrating that you committed academic misconduct (they just don't know whether the misconduct happened back then or now).

The best course of action still available to you would be to resolve the authorship dispute with X prior to any further submissions of the paper. If you cannot come to an agreement with X directly, you may have to involve others, eg your department head. In this, be aware that you will need to own up to your previous mistake.