Falungong members are suing Cisco Systems for custom-building "Golden Shield" Internet technology used by China to track down devotees of the spiritual movement.
Cisco dismissed the case Monday as being without basis and vowed to "vigorously defend" itself.
A lawsuit filed in US federal court in the northern California city of San Jose calls for the computer networking gear giant to pay damages and stop helping China find Falungong supporters.
Cisco "designed, supplied and helped maintain a censorship and surveillance network known as Golden Shield" used by Chinese officials to identify Falungong practitioners who were detained, tortured and sometimes killed, a lawyer for the group said in court documents filed last week.
"Cisco does not operate networks in China or elsewhere, nor does Cisco customize our products in any way that would facilitate censorship or repression," the California-based firm told AFP.
"Cisco builds equipment to global standards which facilitate free exchange of information, and we sell the same equipment in China that we sell in other nations worldwide in strict compliance with US government regulations."
Cisco established a China Network Technology Corp. subsidiary in Beijing in 1998 that went to work on Golden Shield, referred to internally as "Policenet," according to the suit.
"Cisco's specific intent to meet the requirements of the Chinese Communist Party's purpose to identify, track and thereby abuse and eliminate Falungong practitioners... was expressed in marketing presentations," court papers charge.
Explore further: News Corp. to buy Move Inc. for about $950 million