Mr Muriuki was attacked at Hotel Boulevard on April 30 this year.
They denied the charge of violently robbing Mr Muriuki of Sh100,000 during the attack.
Three more suspects have been charged over the attack on Nairobi businessman Timothy Muriuki at a Nairobi hotel, bringing to seven number of people arraigned over the assault.
Mr Muriuki was attacked at Hotel Boulevard on April 30 this year while he was addressing a press conference on the state of the Nairobi County.
On Wednesday, the three suspects, Mr Michael Banya Wathigor, Mr Bernard Onganyo Otieno and Mr Benjamin Peter Mulinge, denied the charge of violently robbing Mr Muriuki of Sh100,000 during the attack.
They appeared before Chief Magistrate Francis Andayi, who released them on Sh200,000 cash bail and consolidated the case with those of four others charged over the same incident.
The cases will be mentioned on May 23, with the hearing set for July 17 this year.
On Tuesday, the fourth suspect, Mr Brian Shem Owino, was also arraigned at the Milimani court where he denied the charge and was freed on Sh200, 000 cash bail.
The three others accused in the case over the attack are: East African Legislative Assembly MP Simon Mbugua, Mr Anthony Otieno Ombok, alias Jamal, and Mr Benjamin Odhiambo Onyango, alias Odhis. They were also freed on Sh200, 000 cash bail each.