The maker of a Web filter backed by the Chinese government plans legal action against U.S. researchers who say its program may have been copied from foreign software, according to state media.
The Chinese program, called Green Dam Youth Escort, appears to use blacklists taken from a filter product made by U.S.-based Solid Oak Software, according to the report by researchers at the University of Michigan. China has ordered copies of the program to be distributed with all PCs sold in China after July 1.
"I think the negative comments and attacks on Green Dam are intentional," the China Daily quoted Bryan Zhang, general manager of the company that designed Green Dam, as saying on Monday.
"It is not responsible to crack somebody's software and publish the details, which are commercial secrets," Zhang was quoted as saying.
Zhang denied any theft of programming code from CyberSitter, the U.S. program, but said the two programs might have similar blacklists since both mainly filter pornography, according to the paper.
No details of the legal action planned by Zhang's company, Jinhui Computer System Engineering, appeared in the report. Zhang says his program, like CyberSitter, is aimed at parents.
China has said Green Dam is meant only to filter Internet porn, but the program also blocks Web sites that mention political terms like Falun Gong, a spiritual movement banned as a cult in China.
Green Dam includes a configuration file that links to lists of banned content from the CyberSitter Web site, according to the U.S. report. The program also includes an encrypted CyberSitter news bulletin from 2004 and a setup file that references the CyberSitter blacklists, the report says.
Calls to Zhang and his company, Jinhui Computer System Engineering, went unanswered Monday evening.