Six former inmates at Highpoint have appeared in court to deny involvement when violence allegedly broke out at the Suffolk jail.
The men, who are now being held at other prisons, have all pleaded not guilty to a charge of affray.
The incident is said to have occurred at HMP Highpoint at Stradishall, near Haverhill, on January 24 last year and to have involved a number of prisoners who were fighting.
On Friday the men appeared before Judge Martyn Levett at Ipswich Crown Court for a plea and case management hearing.
They were Edmund Francis, 23, Mohamed Ahmed, 33, Levi Dawkins, 30, Samir Lammali, 36, Mohamed Tribak, 29, and Dominic Fritz-Campbell, 25.
Judge Levett told the men that their trial, expected to last for up to seven days, will take place in early June.