In a blog post on Thursday, YouTube said it had “removed tens of thousands of QAnon videos and terminated hundreds of channels” under its existing content rules.
But citing challenges in managing “shifting and evolving” content, YouTube said it was necessary to take “another step in our efforts to curb hate and harassment”.
“Today we’re further expanding both our hate and harassment policies to prohibit content that targets an individual or group with conspiracy theories that have been used to justify real-world violence,” it said.
One example, YouTube said, “would be content that threatens or harasses someone by suggesting they are complicit in one of these harmful conspiracies”.
YouTube’s new rules, which represent an expansion of the platform’s hate-speech policy, come three years after QAnon first appeared.The movement has been linked to numerous false claims that have spread online, with the baseless accusations most commonly directed at Democrats.
President Trump has used his Twitter feed to promote unsubstantiated allegations pushed by accounts linked to the QAnon conspiracy theory.
During a meet-the-voters TV event Thursday, the president was asked about the conspiracy theory and replied: “I know nothing about QAnon.”
QAnon is a wide-ranging unfounded conspiracy theory that President Trump is battling a clandestine “deep state” network of political, business, media and entertainment elites, often involving Satanic plots and child trafficking.
QAnon began in October 2017 on the anonymous message board 4chan. An anonymous user left a series of posts on 4chan claiming to be involved in a secret investigative team led by President Trump.