Marzooq, a former MP for the main Shiite opposition movement Al-Wefaq, was arrested on September 17. He has been out on bail since his trial began on October 24 but prohibited from travelling abroad.
Marzooq was in court for the verdict, along with representatives of the opposition as well as delegates from the embassies of Britain, France, Germany and the United States.
The prosecutor had accused Marzooq of using his position at Al-Wefaq, which is an authorised political association, to "call for crimes that are considered terror acts under the law," according to an initial list of charges.
It said that Marzooq had raised the flag of the clandestine group at a public rally after it was handed to him by a masked man.
Marzooq was deputy speaker in the 40-member parliament of the Sunni-ruled monarchy before 18 MPs from the influential Al-Wefaq walked out in February 2011 in protest over violence against demonstrators.
Shiite-led protests erupted on February 14, 2011 in Bahrain, taking their cue from Arab Spring uprisings elsewhere in the region and demanding democratic reforms in the absolute monarchy.
Bahrain, a strategic archipelago just across the Gulf from Iran, is the home base of the US Fifth Fleet and Washington is a long-standing ally of the ruling Al-Khalifa dynasty.
