Justice Chiwendu Nwogu nullified the congresses in his ruling on Wednesday.
Nwogu also stated that the process leading to the emergence of Mr Ojukaye Flag-Amachree as Rivers Chairman of APC was fraudulent.
He said that the APC should return to the status quo of May 11, 2018, pending the determination of the substantive suit and adjourned until June 26 for further hearing.