MDPI publishing house and its associated journals are currently in varying level of disrepute in the academic world due to their peer reviewing practices and special-issue based publishing model. It has been included or discussed for inclusion in predatory journal lists.

This market will resolves Yes, if, by end of 2026, MDPI is perceived to no longer be controversial (not necessarily have good journals, but not be associated with predatory practices). This is judged by absence of inclusion on predatory journal lists by Jan 1. 2027, review of news surrounding retractations and peer review failure scandals, plus a general, if somewhat subjective, vibe check by yours truly of the perception of the journal by then.

Resolves No if practices continues as-is, or get worse, or MDPI is included in further predatory journal list, or embroiled in more scandals.

In case of ambiguity, will discuss with stakeholder in the comments by closure date. May resolve N/A if I don't judge a near consensus to be obtained. I will try to resolve in the spirit of the question, but bettors should take heed of the inherent resolution risk associated with subjectice reputational judgements.