TikTok internal documents viewed by The Guardian showed that the short-form video app was instructing moderators to censor political content considered likely to anger the Chinese government.

Videos that criticized the socialist system or mentioned Tiananmen Square or "highly controversial topics" such as Tibetan independence were banned.

TikTok said the guidelines were outdated and had been revised in May.

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TikTok, the buzzy spiritual heir apparent to Vine, has a history of censoring political content in line with the Chinese government, internal documents viewed by The Guardian reveal.

The documents, which provided guidelines for TikTok's moderators, broke infringing content into two categories: "violations" and "visible to self." Violations would result in the content being taken down, while videos marked "visible to self" would be viewable by the user who posted them but invisible to everyone else on the app.

The specific policies addressing political issues considered likely to anger the Chinese government were embedded in sections designed to look more all-purpose, according to The Guardian.

Bans on politically subversive content were listed in the documents and would result in the videos being made "visible to self" including:

Criticizing China's socialist system was incorporated in a ban on "criticism/attack towards policies, social rules of any country, such as constitutional monarchy, monarchy, parliamentary system, separation of powers, socialism system."

The "demonization or distortion of local or other countries' history." Examples listed included the May 1998 riots of Indonesia, the Cambodian genocide, and Tiananmen Square.

"Highly controversial topics" were banned. These included "separatism, religion sects conflicts, conflicts between ethnic groups, for instance exaggerating the Islamic sects conflicts, inciting the independence of Northern Ireland, Republic of Chechnya, Tibet and Taiwan and exaggerating the ethnic conflict between black and white."

While these blanket bans resulted in the milder "visible to self," posts promoting Falun Gong were deemed an outright violation. Falun Gong is system of spiritual beliefs that is classed as an illegal cult in China. TikTok's rationale for banning Falun Gong was that it was a "group promoting suicide." In 2001, five people self-immolated in Tiananmen Square, and the Chinese media linked them to Falun Gong and the incident was used by the government to argue that Falun Gong was a dangerous cult.

Tiananmen Square was deemed a "demonization or distortion of local or other countries' history" under TikTok's rules. Bettmann / Getty Images

For unclear reasons, the guidelines also forbade specific mention of a list of 20 current and former world leaders including Kim Jong Il, Kim Il Sung, Mohandas Gandhi, Vladimir Putin, Donald Trump, Barack Obama, Kim Jong Un, Shinzo Abe, Park Geun-hye, Joko Widodo, and Narendra Modi. Chinese Premier Xi Jinping was not on the list.

John Jones, the head of advocacy at Free Tibet, told Business Insider that the documents were "alarming but not surprising."

"At a time when digital campaigners around the world are raising concerns over the use and abuse of digital technology, the Chinese government is using its power to regulate freedom of expression to the point that it scarcely exists," Jones said.

"Under Chinese Communist Party rule, sensitive subjects like Tiananmen Square and Tibetan independence are routinely suppressed. Shielding the public from 'dangerous' topics, information and ideas through censorship shrinks the space for dissent and also denies Tibetans of a means to express their culture and identity. Only the CCP's vision can be tolerated," he added, referring to the Chinese Communist Party.

Yaqiu Wang, a researcher at Human Rights Watch, also said she was unsurprised by the news. "All major Chinese companies are directly accountable not only to their management, but also to the Chinese Communist Party. The overt political alignment of companies with the Xi Jinping leadership has increased in recent years," she told Business Insider.

"The difference is that Tik Tok is an app widely used by young people across the world, thus its censorship has global free speech implications. Now the Chinese government is not only able to censor people in China, but also people around the world," she added.

Read more: Inside the rise of TikTok, the Chinese video-sharing app that's currently the No. 1 iPhone app in the US

TikTok's parent company, ByteDance, said in a statement that the guidelines were outdated and had been scrapped in May.

Here is ByteDance's full statement:

"In TikTok's early days we took a blunt approach to minimizing conflict on the platform, and our moderation guidelines allowed penalties to be given for things like content that promoted conflict, such as between religious sects or ethnic groups, spanning a number of regions around the world.

"As TikTok began to take off globally last year, we recognized that this was not the correct approach, and began working to empower local teams that have a nuanced understanding of each market. As we've grown we've implemented this localized approach across everything from product, to team, to policy development.

"The old guidelines in question are outdated and no longer in use. Today we take localized approaches, including local moderators, local content and moderation policies, local refinement of global policies, and more. We also consult with a number of independent local committees and are working to scale this at a global level, including forming an independent committee of leading industry organizations and experts to continually assess these policies.

"We also understand the need to be more transparent in communicating the policies that we develop and enforce to maintain a safe and positive app environment. Users gravitate to TikTok because it provides an app experience that fosters their creativity, and we are committed to supporting that across our teams, product, policies, and the way in which we openly communicate with our community."

ByteDance bought the American lip-syncing app Musical.ly in 2017 for $1 billion and combined it with the company's existing short-form video app, Douyin, to create TikTok as it is now. It soon started to take off, especially with users from Generation Z, and rising to become the top free nongaming iOS app in 2018.

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