Club owners Jeffrey and Michael Derderian and Great White tour manager Dan Biechele were each charged with 200 counts of involuntary manslaughter â€“ two for each death.
All three men pleaded innocent.
"They are not criminals. They did not commit any criminal acts and they should not be charged with any crime," Jeffrey Pine, attorney for Jeffrey Derderian, told AP.
After the blaze, Rhode Island lawmakers passed tough new fire-safety standards, including stricter rules on sprinkler requirements for older buildings. The club had passed its last inspection just two months before the fire.