This article documents how a serial plagiarism case discovered over a decade ago continues to generate negative effects in the downstream research on medieval and early modern philosophy. The ongoing positive citation of the 40 plagiarizing articles and book chapters – including those retracted by their publishers – affects the reliability of later scholarship in several ways. The present state of affairs is the joint result of authors, editors, peer reviewers, and publishers who continue to allow (and in some cases, (...) support) the publication of new works across a variety of genres that contain positive citations to the 40 plagiarizing articles and book chapters. The problem shows no signs of abating; the plagiarizing articles and book chapters continue to acquire positive citations in new publications, including authoritative reference works. The breach of research standards is further shown by the fact that even a non-existent publication by the plagiarist continues to acquire positive citations. (shrink)