MDPI (Multidisciplinary Digital Publishing Institute)

MDPI stands for Multidisciplinary Digital Publishing Institute — a Basel, Switzerland-headquartered academic publisher founded in 1996 that operates several hundred peer-reviewed, fully open-access journals spanning the sciences, social sciences, and humanities. This entry explains what MDPI is, how its publishing model works, and summarizes the genuine, well-documented debate in the scholarly community about editorial rigor at some of its titles — citing real sources rather than asserting a verdict either way.

What MDPI is

MDPI is a commercial publisher, not a scholarly society or a single journal. It publishes exclusively open access under an Article Processing Charge (APC) model: authors (or their institutions/funders) pay a publication fee, and in exchange the article is freely readable by anyone on publication, typically under a Creative Commons license, with no subscription paywall. Well-known MDPI titles include International Journal of Molecular Sciences (IJMS), Sustainability, and Nutrients, among several hundred others. MDPI is a member of the Committee on Publication Ethics (COPE) and of the Open Access Scholarly Publishing Association (OASPA), both of which review member publishers against stated ethical and transparency criteria.

How MDPI journals are structured

Most MDPI journals rely heavily on themed Special Issues: a guest editor (often an active researcher rather than in-house staff) proposes a topic, invites submissions from the field, and manages review for that issue, working alongside the journal’s regular editorial board. This structure has let MDPI scale to a very large annual article volume across its portfolio, and is closely tied to why the publisher is associated with comparatively fast turnaround: MDPI journals are widely reported to have shorter median times from submission to first decision and to final publication than many long-established subscription journals in the same fields, which follows in part from a large reviewer and guest-editor pool working in parallel across many concurrent Special Issues.

The peer review and legitimacy question

MDPI journals use peer review; publication is not automatic on submission. For a full walkthrough of how MDPI’s review process is described and how to check a specific title, see CASRAI’s guide, Is MDPI Peer Reviewed?. On the predatory-publisher question specifically: MDPI was added to Jeffrey Beall’s list of predatory publishers in February 2014, then formally removed in October 2015 following an appeal that both Beall’s own appeals process and a separate OASPA membership review concluded met OASPA’s membership criteria. MDPI has remained an OASPA member since. That specific historical episode is a settled part of the record, not an open question — but it does not mean every MDPI journal is beyond scrutiny today, and it should not be cited as though it settles quality questions about any individual current title.

The genuine, ongoing debate

Separately from the Beall’s-list history, MDPI’s rapid growth and Special-Issue model have drawn documented, specific criticism and scrutiny from indexing bodies and parts of the research community:

• Web of Science discontinuations. In March 2023, Clarivate discontinued Web of Science coverage of two MDPI journals — International Journal of Environmental Research and Public Health (IJERPH) and Journal of Risk and Financial Management (JRFM) — citing its ‘Content Relevance’ evaluation criterion, as part of a broader review that also removed dozens of titles from other publishers (including numerous Hindawi journals) that same cycle. MDPI publicly confirmed the decision and appealed the IJERPH removal.
• National research-assessment flags. Around 2021, a number of MDPI journals were affected by Norway’s national Publication Indicator, which places journals it assesses as not meeting its criteria into a non-counting ‘Level X’ category; this reflected concerns from Norwegian research-assessment bodies specifically about Special-Issue-driven volume growth.
• High acceptance rates and short review times at some titles. Critics, including researchers writing in venues such as Nature’s news pages and the scholarly-communication commentary site The Scholarly Kitchen, have raised concerns that the volume and speed achievable through the Special Issue model create pressure that can work against review depth at some journals and in some issues, and have questioned self-citation patterns at specific titles. These are documented concerns about specific journals, editors, or issues — not a finding that MDPI as a whole is predatory or that its peer review is fabricated.

Taken together, the accurate, balanced summary is: MDPI is a real, large, COPE- and OASPA-member open-access publisher whose predatory-list history is closed and resolved, but whose scale and Special-Issue model have also produced specific, ongoing, and legitimate editorial-quality questions at particular journals — documented through indexing-body decisions (Web of Science, national assessment bodies) rather than through blanket predatory-publisher classification. Neither ‘MDPI is predatory’ nor ‘MDPI’s scrutiny is unfounded’ is an accurate one-line summary; both overstate a more specific, journal-by-journal reality.

How to evaluate a specific MDPI journal

Because quality varies by title, treat ‘published by MDPI’ as a starting point for due diligence, not a verdict in either direction. Useful checks: confirm the specific journal’s current Web of Science / Scopus indexing status directly (rather than assuming the publisher’s overall reputation applies); check the journal’s Journal Impact Factor and CiteScore trend and quartile rather than a single undated figure; review the editorial board’s composition and the guest editor’s track record for a Special Issue you are submitting to or citing from; and weigh these alongside discipline norms, since APC-funded, fast-turnaround publishing is now common well beyond MDPI. See CASRAI’s DORA (San Francisco Declaration on Research Assessment) entry for the broader case against relying on any single publisher- or journal-level signal as a proxy for the quality of an individual article or author.