SECTION 8. Proscription of an Organization. – For the purpose of this Act and with the observance of due process, the Anti Terrorism Council, upon its own initiative, or upon recommendation of the Secretary of Justice may proscribe a group as a terrorist organization if such organization is characterized by-any of the following:
1. Any member or members thereof openly and publicly declares, admits, acknowledges, to have committed any of the acts punishable under this Act;
2. Any member or members thereof have been convicted for the commission of any act of terrorism as defined and described in Sections 3, 4 and 5 of this Act;
3.1t is proscribed by the United Nations or international organizations.
Proscriptions shall be published in the government gazette and major newspapers.
Any proscribed organization or member thereof may move for de-proscription or to de-listing before the Department of Justice (DOJ), whose decision is appealable to the Court of Appeals.
link to the complete text of the Anti-Terrorism Act: Philippines-Anti-Terrorism Act-2005-eng