A Swiss sample archive grew into a giant of open-access science
MDPI began in 1996 as a Basel archive for swapping rare chemical samples. By 2020 it was the world's largest publisher of open-access papers, turning out well over 200,000 articles a year. Its speed has made it hugely popular with authors and deeply divisive among scientists, who argue over whether fast also means careless.
Chemist Shu-Kun Lin and Benoit Turin registered Molecular Diversity Preservation International as a non-profit association in 1996. To document its sample collection it launched the journal Molecules with Springer, then added titles such as Entropy and Sensors. In May 2010 the publishing arm was spun off as the Multidisciplinary Digital Publishing Institute, headquartered in Basel with offices in 11 countries, including five in China. Every journal is open access, free to read, with authors or their funders paying processing charges.
Growth was explosive. Output rose by more than 50% a year in 2017, 2018 and 2019, reaching 110,000 papers in 2019 and 235,638 in 2021. By January 2024 it ran 433 journals. The engine is the special issue: collections on a theme run by guest editors rather than regular board members, often with invited papers. Around 88% of its papers appear this way, and special issues jumped from 6,756 in 2020 to 39,587 in 2021, though only 10,504 of the latter published anything.
Critics say the model trades rigour for speed. Librarian Jeffrey Beall put MDPI on his list of predatory publishers in 2014, citing lightly reviewed papers and spam invitations; it was removed after an appeal in 2015, and Beall later said MDPI helped pressure his university until the list closed in 2017. In 2018 ten senior editors of Nutrients resigned, alleging pressure to accept mediocre work, and in 2024 Finland's Publication Forum dropped 193 MDPI journals to its lowest rating.
The picture is not one-sided. An open-access trade body investigated in 2014 and found MDPI met its membership standards, and in 2013 its journal Cancers rejected a fake paper sent in a famous sting on sloppy peer review. By 2025 the Chinese Academy of Sciences listed no MDPI journals on its early-warning list.
Source: MDPI
