A Suez court sentenced twenty alleged Muslim Brotherhood members to three years in prison, fining them 50,000 Egyptian pounds each, on Wednesday for breaking the protest law.
The defendants were also charged with joining demonstrations that incite violence, carrying weapons and fireworks and protesting against the army and police.
The authorities arrested the defendants in recent clashes between supporters of ousted President Mohamed Mursi and police forces and residents in Suez.
The clashes followed the dispersal of two sit-ins supporting Mursi.