In our critique of a pay-to-participate study, we address how the failure to disclose study-related payments appears to have violated STEM CELLS Translational Medicine's editorial policies concerning conflict-of-interest and financial disclosure. Our analysis also identifies broader ethical issues and scientific concerns related to pay-to-participate studies conducted by businesses with a record of selling purported stem cell treatments before determining whether the products they sell are safe and efficacious. Authors of peer-reviewed articles have a responsibility to comply with journal policies and disclose financial conflicts of interest to editors, reviewers, and readers. Authors should also disclose when stem cell interventions being tested in clinical trials have already been sold on a direct-to-consumer basis as "stem cell treatments" by authors' affiliate institutions. Financial conflicts of interest and other forms of possible bias must be disclosed to put clinical studies in context and facilitate the critical assessment of research methods, findings, and conclusions. The apparent failure to comply with journal editorial policies and disclose such financial conflicts warrants careful investigation.