Giza Criminal Court has postponed the trial of prominent activists Alaa Abdel-Fattah and Mona Seif until 3 September.
They are accused, along with 11 others, of burning the headquarters of Ahmed Shafiq during his presidential election campaign in May 2012.
The prosecution says the activists stormed Shafiq's campaign office, destroyed some of its contents and burned campaign posters.
All 13 defendants are free until the trial resumes.
