Attorneys for Chinese activist Ning Xianhua filed a lawsuit in the U.S. District Court in San Jose, Calif., alleging that Yahoo Inc. founder Jerry Yang and CEO Terry Semel provided Xianhua's Yahoo emails to Chinese authorities in exchange for commercial access to more than 100 million Chinese internet users.

According to the lawsuit, Xianhua used his Yahoo email account to spread "pro-democracy messages and publications" that he believed to be secure. However, Yahoo enabled the Chinese government to monitor its citizens' emails through several confidential agreements, which led to Xianhua's "capture, imprisonment, and torture" by Chinese government officials.

Yahoo's successor companies, Oath Holdings Inc. and Altaba Inc., are also named as defendants in the case, according to a Sept. 2 news release. Oath Holdings is a division of Verizon Communications Inc.