Green Dam Youth Escort (Chinese: 绿坝·花季护航; pinyin: Lǜbà·Huājì Hùháng) is content-control software for Windows developed in the People's Republic of China (PRC) which, under a directive from the Ministry of Industry and Information Technology (MIIT), was to take effect on 1 July 2009, as a mandatory pre-install, or have the setup files on an accompanying compact disc, for all new personal computers sold in mainland China, including those imported from abroad.

[2] The software, commissioned by the Ministry of Industry and Information Technology through open tender worth 41.7 million yuan in May 2008,[8] is at least officially aimed at restricting online pornography; however, it may be used for electronic censorship and surveillance in addition to its stated purpose.

[9][10] Green Dam Youth Escort automatically downloads the latest updates of a list of prohibited sites from an online database, and also collects private user data.

Qin Gang, spokesman for the foreign ministry, said the software would filter out pornography or violence: "The purpose of this is to effectively manage harmful material for the public and prevent it from being spread," adding that "[t]he Chinese government pushes forward the healthy development of the internet.

[1] In June 2009, state-run Chinese media announced that the installation of the Green Dam Youth Escort would not be compulsory but an optional package.

[15] In 2008, under instructions from political leaders, the MIIT implemented a "community-oriented green open Internet filtering software project" with the support of the Central Civilisation Office and the Ministry of Finance.

Five leading PC vendors in mainland China, Founder, Lenovo, Tongfang, Great Wall and HEDY, also participated in trial installations.

Ed Black, CCIA president criticised the move as "clearly an escalation of attempts to limit access and the freedom of the internet, [...with] economic and trade as well as cultural and social ramifications."

[22] The CCIA was reported to be taking up a test case for American tech companies wishing to present "a united front against censorship" and it called on the Obama administration to intervene with Beijing over the requirement that manufacturers pre-install the software on all new computers.

However, "[i]n this case, we agree with others in industry and around the world that important issues such as freedom of expression, privacy, system reliability and security need to be properly addressed.

"[24][25] An international group of business associations urged the government to scrap the Green Dam directive in a letter to Chinese Premier Wen Jiabao.

[26] In moves which the San Francisco Chronicle suggested were politically motivated by the quest for closer ties, Taiwanese manufacturers Acer, Asus, BenQ announced they were already shipping products with Green Dam as originally ordered, joined by Sony and Lenovo.

[31][32] On 11 June 2009, a team released a third-party tool aiming to provide users with options to disable the software, change the master password and perform post-uninstallation clean-up (i.e., removing files and registry entries left behind by the uninstaller).

Reports in defense of the official stand appeared subsequently, with a commentary by the state-run Xinhua news agency saying "support largely stems from end users, opposing opinions primarily come from a minority of media outlets and businesses".

Ministry sources confirmed that the software had been patched, and that the government procurement procedure of the software "had complied with China's Government Procurement Law, which was open, fair, transparent, non-exclusive, [...] under strict supervision" and "in line with regulations of the World Trade Organization"[41][42] On meeting with officials of the MIIT and the ministry of commerce about Green Dam, American diplomats in China issued a statement: The U.S. is concerned about actions that seek to restrict access to the Internet as well as restrictions on the internationally recognized right to freedom of expression.

"We have asked the Chinese to engage in a dialogue on how to address these concerns.Jinhui claimed that Green Dam recognized pornographic images by analyzing skin-coloured regions, complemented by human face recognition.

On 11 June 2009, Scott Wolchok, Randy Yao, and J. Alex Halderman from the University of Michigan published an analysis of Green Dam Youth Escort.

[50] In addition to security vulnerabilities, Wolchok, Yao and Halderman also found that a number of blacklist files used by Green Dam Youth Escort were taken from the censorship program CyberSitter, from Solid Oak Software Inc.

[48] According to The Wall Street Journal, Solid Oak, which had been apprised of the infringement, announced it would file injunctions on US manufacturers to stop them shipping machines with Green Dam.

[52] Solid Oak's Mr Milburn was reported by BBC News as saying that he is not sure legal action will be worth the effort, but would also file a complaint with the Federal Bureau of Investigation's Computer Crime Task Force.

[10] Hewlett-Packard and Dell were sent cease and desist letters by Solid Oak Software, asking them to respond by 24 June, having determined "without a doubt that Green Dam is indeed pirated, and using 100 percent of our code".

The motion was filed by Sony, Acer, BenQ and Asustek, who were named as defendants in a list that also includes Chinese PC makers Lenovo and Haier.

[58] In 2010, other commentators, whilst noting no change in the government's policy towards policing the Internet, said the de facto abandonment of the project was an admission of error.