The court, however, upheld a fine of over USD 11,200 for each defendant yesterday, according to judicial sources.
The defendants were referred to court last month for "illegally protesting, attempting to overthrow the government, rioting, inciting against state institutions, disturbing public peace".
Several activists rallied on April 25 to protest against the government's decision to transfer the two Red Sea islands of Tiran and Sanafir to Saudi Arabia. The islands were under Egyptian control for over 60 years.
Police had arrested a number of protesters and used tear gas to break up the protest believed to be the largest to take place in Egypt since President Abdel-Fattah El-Sisi was elected as president in 2014.
According to a controversial protest law issued in 2013, street protests are banned in Egypt without prior permission from police.