In 2022 a Swiss programmer from Lausanne, Solal Pirelli, while going through the proceedings of conferences held under the aegis of the Association for Computing Machinery, discovered systematic anomalies in volumes published under the chairmanship of the

In 2022 a Swiss programmer from Lausanne, Solal Pirelli, while going through the proceedings of conferences held under the aegis of the Association for Computing Machinery, discovered systematic anomalies in volumes published under the chairmanship of the Jordanian computer scientist Shadi Aljawarneh of the Jordan University of Science and Technology. The anomalies included excessive citation of Aljawarneh in the prefatory sections of the collections, individual papers that cited him more than a hundred times, and a conference supposedly held in Kazakhstan at the height of the Covid lockdown. In October 2022 Pirelli sent a first report on the problems to the organisation, received no reply, and in January 2023 published a detailed analysis of what was going on on his own blog. Soon after the publication Aljawarneh asked Pirelli to delete the post, but offered no specific rebuttals, confining himself to the general formula "you are wrong".

The reaction of the academic community was immediate: an April 2023 conference involving Aljawarneh was cancelled, and he himself was removed from the editorial board of the journal PeerJ Computer Science.

In November 2023 Pirelli learnt that Aljawarneh had brought a defamation suit against him in Switzerland through a Geneva law firm, and had attached Pirelli's article to the case as evidence of reputational harm. In June 2025 the district court of Lausanne found Pirelli guilty of defamation, ruling that the blog "is not limited to criticism of the quality of the work, but plainly imputes scientific fraud".

Pirelli appealed, and in October 2025 he received a letter stating that the organisation had completed its investigation and found "clear and convincing evidence" of repeated violations of its publication policy by Aljawarneh. As a result of the investigation the ACM retracted 38 papers connected with the case and imposed additional sanctions on Aljawarneh, the content of which has not been made public. The criminal appeals court of the canton of Vaud, in January 2026, overturned the verdict of the court of first instance, concluding that "the plaintiff's deliberate conduct in falsifying and inflating citations may indeed be broadly characterised as scientific fraud".

The detailed reasoned judgment, published on 1 May 2026, obliged Aljawarneh to reimburse Pirelli's legal costs: 19,967 Swiss francs for the first instance and 7,044 francs for the appeal. Aljawarneh has thirty days from 1 May in which to appeal to the Swiss Federal Supreme Court, while Pirelli goes on combing the literature for citation anomalies, and states his motive thus: articles in journals that nobody reads do not trouble him, but clownery in the proceedings of the very publisher that also publishes his own work strikes at his own reputation.