Hash sharing: Violent Extremism
YouTube utilizes technology to prevent re-uploads of known violative content before that
content is available to the public. We have long used this technology to prevent the spread
of child sexual abuse imagery on the platform. In 2016, we created a
hash-sharing database with industry partners where we share hashes (or “digital
fingerprints”) of terrorist content to stop its spread. The shared database currently
contains more than 400,000
unique hashes that are near-identical to the human eye.
YouTube's vast media library and automated
detection systems make us a large contributor of hashes to the hash-sharing database.
In accordance with the sharing criteria established by the Global Internet Forum to Counter
Terrorism, YouTube contributed over 45,000 unique hashes to the hash-sharing database in 2023.
Once content has been hashed, other platforms can use those hashes to help detect related content on their platforms and assess it against their own content policies. Since 2017, the number of companies contributing to and benefiting from this database has grown from 4 to 13. This organized effort is now formally operated by the Global Internet Forum to Counter Terrorism (GIFCT).
Global Internet Forum to Counter Terrorism: Violent Extremism
In 2017, YouTube, Facebook, Microsoft, and Twitter founded the Global Internet Forum to Counter Terrorism (GIFCT) as a group of companies, dedicated to disrupting terrorist abuse of members’ digital platforms. Although our companies have been sharing best practices around counterterrorism for several years, GIFCT provided a more formal structure to accelerate and strengthen this work and present a united front against the online dissemination of terrorist content. In collaboration with the Tech Against Terrorism initiative, GIFCT hosts global workshops, engaging tech companies, non-governmental organizations, and international government bodies.
With varied members and industry partners using the hash-sharing database, there needed to be a baseline consensus for what would constitute terrorist and extremist content for the purposes of reviewing and sharing hashes of content. As noted in GIFCT's 2021 Annual Transparency Report, “the original scope of the hash-sharing database is limited to content related to organizations on the United Nations Security Council's Consolidated Sanctions List.”
YouTube and GIFCT's other founding members signed on to the Christchurch Call to Eliminate Terrorist and Violent Extremist Content Online. Building on the Christchurch Call, GIFCT developed a new Content Incident Protocol (CIP) for GIFCT member companies to respond efficiently to perpetrator-created, live-streamed content after a real-world, violent event. This protocol has been tested and proven effective-for example, following the attack on a synagogue in Halle, Germany (October 2019); a shooting in Glendale, Arizona, US (May 2020); a shooting in Buffalo, New York, US (June 2022); and a shooting in Memphis, Tennessee, US (September 2022). Since creating the CIP, GIFCT has further developed its Incident Response Framework to include a Content Incident tier to respond to non-live-streamed, perpetrator-produced video and images depicting the real-world event. This was activated for the first time following an attack in Udaipur, Rajasthan, India (July 2022).
GIFCT has evolved to be a standalone organization with an independent Executive Director and staff. GIFCT's structure also includes an Independent Advisory Committee composed of government representatives and non-governmental members, including advocacy groups, human rights specialists, researchers and technical experts. Within the new governance framework of the institution, YouTube holds a position on GIFCT's Executive Operating Board.