Analysis: An intern took on one of China's stars in a #MeToo case. She lost, but vowed to fight on
Sexual harassment lawsuits were rarely seen in China at the time, and Zhou's case was widely regarded a barometer for the country's progress on addressing entrenched gender inequality.
A court in Beijing ruled against her after a long-delayed second hearing, citing "insufficient evidence."
Zhu, 57, is a former member of the Chinese People's Political Consultative Conference, a top political advisory body to the Chinese government.
Despite rising awareness about gender equality, young feminists in China face increasingly stringent censorship, unrelenting state harassment and misogynist attacks from online nationalists .
Zhou's account on Weibo, China's Twitter-like platform, was suspended in July for violating "Weibo complaint regulations."
You've already done so much," her supporters shouted in reply, according to videos shared by people at the scene.
Zhou Xiaoxuan, known also as Xianzi, stands with supporters outside a Beijing court on September 14.
Zhou's case is a reality check for China's stifled #MeToo movement, which was recently thrust back into the spotlight following two explosive rape allegations involving a top celebrity and a tech giant.
"Zhu Jun is powerful, and it seems like outside political pressure was tipping the scales even further in his favor," he said.
On Weibo, users who shared photos and videos of the scene outside the courthouse and updates on Zhou's case found their accounts suspended for a week or longer.
Lv Pin, a prominent Chinese feminist now based in New York, said over the past three years, Zhou's case sparked public discussions and significantly raised social awareness about sexual harassment.
In the small hours on Wednesday, Zhou posted a statement on Chinese social media app WeChat pledging to continue her fight to her supporters online.