Springer Nature retracts 75 studies by Spanish rector and his collaborators for fraudulent practices

Springer Nature, one of the world’s leading scientific publishers, has abruptly retracted 75 scientific papers authored by Juan Manuel Corchado, the rector of the University of Salamanca, along with his collaborators. The multinational company initiated an investigation in May after EL PAÍS revealed internal messages indicating that Corchado had requested his employees add citations to his work in their papers to create the illusion that he was among the most cited scientists globally, a practice that had been going on for years. The scale of these retractions — unprecedented in Spain — makes Corchado’s case the largest known scandal among Spanish scientists.

Chris Graf, director of scientific integrity at Springer Nature, says that the retraction of the 75 studies is underway. “Our investigations identified various concerns, including, but not limited to, compromised editorial handling, inappropriate or unusual citation behavior, and undisclosed competing interests,” says Graf.

Corchado’s group organized numerous conferences and utilized the related papers — published by Springer Nature — to artificially inflate the number of citations to the rector, even when those references were irrelevant to the subject matter. This newspaper reported in May that, across just 75 publications, Corchado’s collaborators cited him nearly 1,700 times, a tactic that propelled him into international rankings as one of the most cited scientists in his field.

Some studies have already been retracted, such as a paper on a technology to classify odors, authored by Corchado which includes 10 citations to his own work, as well as another paper by his collaborator Pablo Chamoso on counting animals using drones, which included 22 citations to the Salamanca professor.

Chris Graf emphasizes that Springer Nature takes the complaints it receives very seriously: “Citations are an important element of academic research, not least for accurately acknowledging sources, providing context, offering evidence, creating a research trail for the benefit of other researchers, and evaluating impact. It is essential that they are applied appropriately and responsibly.”

Ramón López de Mántaras — one of the pioneers of artificial intelligence in Spain — has urged the rector to accept the reality of the situation. “I have always had a very cordial relationship with Corchado, which is why I feel so disappointed that he has fallen into the trap of inflating his bibliometric indicators. If he had sought my advice, I would have recommended that he acknowledge his mistake instead of evading responsibility and to withdraw his candidacy for rector to avoid harming his university,” he says.

A report commissioned by the Spanish Committee on Research Ethics in September confirmed the “deliberate” and “systematic” manipulation of Corchado’s CV. The 131-page document, authored by Emilio Delgado and Alberto Martín — two researchers from the University of Granada who are experts in academic integrity —concluded that Corchado and his collaborators established “a publication and citation factory” employing “strategies based on questionable publishing conduct and bad editorial practices, if not outright fraudulent behavior.”

Corchado’s response was a 54-page document titled “In Defense of My Rights,” published on September 30. In this statement, the rector of the University of Salamanca alleges a conspiracy against him involving the Spanish Committee on Research Ethics, EL PAÍS, and the two professors from Granada. However, the manipulative tactics exposed by this newspaper had already made headlines in prominent international media, including Science, Nature, and Times Higher Education.

Ramón López de Mántaras, who founded the Artificial Intelligence Research Institute in Cerdanyola del Vallès in Barcelona three decades ago, commented on the situation: “Anyone with half a brain can see that the report by the Granada experts is impeccable and well-reasoned. The members of the Spanish Research Ethics Committee that I know uphold irreproachable ethics and morals. The notion of a dark conspiracy is unfounded, it is an absurd argument,” says López de Mántaras, who is the only specialist outside North America to have received the prestigious Robert S. Engelmore Prize.

Spanish virologist Nonia Pariente has been working in scientific publishing for 16 years. She is currently the editor-in-chief of PLOS Biology in Cambridge and previously held the same position at Nature Microbiology in London. “It is incomprehensible that a person with such blatant misconduct can serve as the rector of a university,” she says. “I find it shameful, though not unusual. The way scientists are evaluated is deeply flawed in many places, particularly in Spain. There are individuals who consistently publish poor-quality articles because it benefits them in ANECA evaluations,” she laments. The National Agency for Quality Assessment and Accreditation (ANECA) is the organization in Spain that determines whether a professor is eligible for promotion to full professor or qualifies for a salary increase.

Pariente considers Corchado’s case to be “a disgrace” for Spanish science. “What worries me a lot is that, despite everything, he was elected rector. It is incredible that those who voted for him did not recognize this as a problem. Spanish universities and their rectors need to take action,” she urges. “If I were Corchado, I would resign.”

Corchado dismisses the retraction of 75 studies by his group as “a minor issue.” “We neither agree with nor accept the withdrawal of these articles, which have undergone thorough peer review and contain essential references. Ultimately, the removal of these articles — just a few dozen out of the thousands we have published— represents a minuscule fraction. Specifically, it pertains to about a dozen workshop articles in which I am neither the corresponding author nor the first author, out of nearly a thousand in which I have collaborated,” he stated in his document dated September 30.

Biologist Isidro Aguillo, head of the Cybermetrics Laboratory at the Spanish National Research Council (CSIC), compiles an annual ranking of the most cited Spanish researchers using data from Google Scholar. Corchado was ranked 157th out of a total of 123,000 scientists until he deactivated his profile upon learning that EL PAÍS was investigating his practices. Aguillo expresses strong concern: “I am particularly troubled by the lack of response from the academic community, both locally and nationally. It is regrettable that the culture of impunity shielding endogamous malpractice and nepotism has extended to fraud and manipulation.”

Corchado not only organized what is known as a citation cartel — a group of researchers who collude to cite one another — but he also benefited from approximately 30 fake profiles of fictitious scientists dedicated to massively citing him on the social network ResearchGate. In addition, Corchado, a professor of Computer Science and Artificial Intelligence, uploaded numerous documents filled with self-citations to his university’s scientific repository, GREDOS, including one paragraph on smart buildings that contained 227 citations to his own work.

Thanks to these practices, he claimed to be the fourth most cited scientist in Spain in his field. The second most cited researcher was Enrique Herrera Viedma. A study he co-authored with Corchado — where more than 50% of the citations were to the Salamanca professor — was previously retracted. Herrera assumed the role of rector at the University of Granada in September.

Corchado claims that he is the victim of a defamation campaign. “I have reported threats against my physical integrity received through my personal email, which is linked to my candidacy for rector of the University of Salamanca. These threats, sent from anonymous accounts, contained messages urging me to end my life,” he states. The rector of the University of Salamanca also claims that his identity has been stolen. “All the crimes have been reported to the relevant police and judicial authorities and are currently under investigation, so I cannot provide any further details,” he adds in the document “In Defense of My Rights.”

Epidemiologist Cristina Candal from the University of Santiago de Compostela has dedicated her doctoral thesis to investigating misconduct in scientific research, and she has no doubts about the Corchado case. “This is clearly scientific misconduct. It constitutes a citation cartel aimed at manipulating the system for personal gain. With these inflated metrics, individuals secure more funding and higher salaries. It is completely unfair competition. It is not at all ethical,” she says.

Candal acknowledges that ANECA is taking steps to move away from evaluating scientists on metrics, but she urges for more profound changes. “Corchado is a symptom of the system. These issues occur more frequently than we realize,” she warns.

The expert notes that the Spanish Committee on Research Ethics — an independent body established a year ago by the Spanish government and regional authorities — can issue reports and recommendations, but has limited power. Candal suggests granting it the authority to impose sanctions, similar to the Office of Research Integrity that oversees the public health system in the United States. “When push comes to shove, the ethics committee can do nothing. It’s clear. It’s like traffic cameras that take a photo of you when you speed but don’t issue a fine. If no sanctions are imposed, scientific misconduct will continue,” she says.

Candal believes that Corchado should resign: “Who has the authority to remove the rector? The damage extends beyond him as an individual; he is harming his own institution and the entire Spanish university system. The international media are taking notice. It is quite concerning that Corchado continues to lead one of the most important university institutions in this country.”

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