All year, human-rights and free-speech advocates have been chastising big U.S. Internet companies for helping to censor the Internet in China. Critics of Beijing's policies have focused on Google, Yahoo!, and Microsoft, all of whose search engines operate in China under requirements to filter results from many Web sites related to such things as independence movements in Taiwan and Tibet, democracy advocates, and the Falun Gong religious movement.

In February, congressmen called representatives from the three companies to a hearing on Capitol Hill and berated them for their cooperation with the Chinese government. And London-based Amnesty International has accused them of violating human rights principles (see BusinessWeek.com, 5/25/06, "Amnesty Intl. Sees Red over Yahoo China").

Now Human Rights Watch is trying to turn up the heat another notch. On Aug. 10, the organization, headquartered in New York, came out with a report criticizing the three companies for their role helping to censor the Internet in China. The report is particularly damning of Yahoo, which Human Rights Watch says censors its Chinese site far more vigorously than either Google or Microsoft. Yahoo China is owned by Chinese e-commerce specialist Alibaba.com, but Sunnyvale (Calif.)-based Yahoo owns 40% of Alibaba and has a seat on the Chinese company's board.

"Clearly, it's not just an issue of 'the Chinese government told us to do this and we're just following orders,'" says Rebecca MacKinnon, a former CNN reporter who is now a research fellow at the Berkman Center for Internet & Society at Harvard Law School and helped put together the report for Human Rights Watch. While Beijing officials provide companies with guidelines on what subjects are taboo, sometimes the rules are vague and the government leaves the job of enforcing them to the companies themselves. When it comes to censoring taboo subjects, "different companies are making very different choices," she says.

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