Owsiak sued the blogger, who wrote under the pseudonym MatkaKurka, over three texts posted online in 2013: "Jerzy Owsiak – king of beggars and liars, the golden melon of the WOŚP sect", "Guru Owsiak took out 46 Golden Melons in 11 years" and "Jerzy Owsiak, king of beggars and liars, is working on a new title – cemetery hyena". The head of WOŚP accused the blogger of defaming WOŚP and himself in these publications by alleging that they appropriated money raised through a public collection. In a private indictment, he also accused the blogger of providing unreliable information about WOŚP’s activities, thereby exposing the foundation to a loss of public trust.
The court acquitted Wielgucki (he agreed to the disclosure of his personal details) of the charges concerning the texts "Jerzy Owsiak – king of beggars and liars, the golden melon of the WOŚP sect" and "Guru Owsiak took out 46 Golden Melons in 11 years". However, it found him guilty of insulting the head of WOŚP in the third text, in which Owsiak was called a "cemetery hyena". It nevertheless waived the imposition of a sentence. In its reasoning, the court stated that the facts presented by the blogger in his texts "did not cross the boundary of truth". Assessments of these facts are not subject to criminal law or the charge of defamation because they are opinions. According to the court, the defendant’s individual statements, with the exception of the term "cemetery hyena", did not exceed the limits of permissible criticism of public figures.