Wiley retracted 11,300+ papers and shut down 19 Hindawi journals, losing $35-40M in revenue, because paper mills infiltrated via guest-edited special issues

Between 2023 and 2024, Wiley retracted more than 11,300 papers from its Hindawi portfolio -- more retractions than any single publisher had ever issued. In 2024, Wiley shut down 19 Hindawi-branded journals entirely. The company disclosed $35-40 million in lost revenue from the cleanup. The attack vector was specific: paper mills exploited the guest-edited special issue model, where external academics are invited to curate themed collections. Paper mill operators either became guest editors themselves or bribed existing guest editors, then funneled fabricated manuscripts through compromised peer review. Hindawi's integrity team found duplicated review text, reviewers who turned in reports within hours, and systematic misuse of reviewer databases. The downstream damage extends far beyond Wiley's balance sheet. Thousands of researchers who legitimately published in these journals now have retracted or tainted publications on their CVs -- not because they committed fraud, but because they happened to publish in a journal that was simultaneously being exploited by paper mills. For early-career researchers in developing countries who published in Hindawi journals because APCs were affordable, a mass retraction on their record can be career-ending. Their papers are delisted from indexes, their citation counts drop, and their grant applications are weakened -- all through no fault of their own. They are collateral damage of a publishing model that prioritized volume over integrity. The root cause is the perverse incentive structure of the special issue model. Publishers discovered that special issues generate more submissions (and therefore more APC revenue) than regular issues. MDPI published nearly 40,000 special issues in 2021 alone. Hindawi adopted the same playbook. But special issues delegate editorial gatekeeping to guest editors who have no contractual accountability, no training in fraud detection, and no financial stake in the journal's long-term reputation. The publisher profits from every accepted paper; the guest editor gets a CV line; and nobody has an incentive to reject manuscripts. Paper mills recognized this as the weakest point in the system and exploited it at industrial scale.