One of the 16 defendants in the cabinet clashes retrial has been referred to a juvenile court.
The retrial date for Nema El-Sayed, 18, has not been set and she remains in detention.
The retrial for the 15 other defendants has been postponed until 2 April.
El-Sayed is accused of rioting, inciting chaos, damaging public and private property, possessing bladed weapons and Molotov cocktails, and assaulting personnel from the armed forces and the police
The court said she had not reached the age of 18 at the time of the clashes - she was born on 25 January 1997.
A court sentenced 39 minors to ten years in prison in February and 230 defendants, including activist Ahmed Douma, to life in prison and a LE17 million (US$2.2 million) fine in the same case.
On 16 December 2011, soldiers forcibly dispersed a three-week sit-in against military rule at the cabinet building in downtown Cairo. At least 18 people were killed and hundreds injured in the violence which spanned over five days, events which are now referred to as the 'cabinet clashes'.
As of October 2014, there were 120 minors (all boys under 18) detained in Egypt over politically related incidents.
Egypt passed a controversial protest law in November 2013 that bans protests without a prior police permit.
Since then, many minors have been arrested at unauthorised protests.