Six South Korean activists have filed a lawsuit against Google Inc., demanding that the global tech giant disclose whether it shared their personal information with a third party, a civic group said Wednesday.

Google is suspected of passing on private information of its users, including those that live outside the U.S., to an American government intelligence program known as PRISM, the Citizens' Coalition for Economic Justice (CCEJ) said.

PRISM, which made global headlines after former U.S. intelligence contractor Edward Snowden divulged its existence last year, trawls the Internet for email and chat records of anyone who has contacts in the U.S.

The six plaintiffs from the CCEJ, the Korean Progressive Network Center and the South Korean chapter of Amnesty International lodged the suit with Seoul Central District Court, asking the tech giant to come clean about its data sharing activities.

"Even if Google has servers in the U.S. or other countries, it must abide by South Korean law when dealing with users in South Korea," the CCEJ said in a statement. "Google should therefore respond to South Koreans' requests for information about its history of leaking sensitive data."

Under South Korean law, online service providers must respond to a customer's request to disclose any record of their personal data being shared with a third party.

In February, Google failed to respond to the plaintiffs' request for records of their information being passed on to outsiders, the civic group said. (Yonhap)