Background: The number of Systematic Literature Reviews published in Software Engineering has been increasing in recent years. Due to this fact, one point not addressed is the possibility of plagiarism when dealing with SLRs, especially when dealing with SLR maintenance (update) activities. Aims: To identify what researchers understand by SLR plagiarism, whether the process of maintaining these SLRs can increase the chances of committing plagiarism, and how this misconduct can be avoided. Method: During a previous survey about SLR maintenance, we asked questions about SLR plagiarism issues and also a semi-structured interviews was performed to obtain responses from experts conducting SLRs on possible SLR maintenance plagiarism issues. Also, a comparison between SLR updates and their original works was made, through a plagiarism tool, looking for possible plagiarism situations. Results: The general concern, in the survey and semi-structured interviews, is with study proper citation and what was published by others. We understand, therefore, plagiarism in SLR is not different from other areas of research. However, we have specific situations for the SLR maintenance process that lead us to present a set of good practices to avoid plagiarism. When comparing SLRs updates with their originals, possible plagiarism situations were identified, mainly in the method section, which was expected due to its reuse. Conclusions: Although we do not need a specific plagiarism definition for SLRs when we think in SLR maintenance (update), we understand there is a higher possibility of committing plagiarism without proper care, as identified in the comparisons made between SLRs updates and their original versions. CCS CONCEPTS • General and reference → Empirical studies.