Slack has started blocking users who visited US sanctioned countries

Slack HQ

Communication service Slack is reportedly blocking users with ties to countries that are under sanction by the US government, with immediate effect and no chance of appeal.

Slack said the ban is in response to obligations to US regulations and is aimed at users that have visited countries under US sanctions, such as Iran, Cuba and North Korea.

However, some users claim bans have been made in error as they haven't visited the listed nations in recent years.

A number of users have taken to Twitter to question the company's reasoning and some have even posted screenshots of the messages Slack have sent them explaining why they've been blocked.

"In order to comply with export control and economic sanctions laws and regulations promulgated by the U.S. Department of Commerce and the U.S. Department of Treasury, Slack prohibits unauthorised use of its products and services in certain sanctioned countries and regions including Cuba, Iran, North Korea, Syria, and the Crimea region of Ukraine," said Slack in a message to banned software developer Amir Omidi.

"We've identified your team/account as originating from one of those countries and are closing the account effective immediately."

Underneath the screenshot, Omidi explained that the immediate ban was also undisputable because he couldn't appeal: "So @SlackHQ decided to send me this email. No way to appeal this decision. No way to prove that I'm not living in Iran and not working with Iranians on slack. Nope. Just hello we're banning your account," he Tweeted.

How Slack has determined who to ban is coming under scrutiny with users questioning how they know if they've visited any of the sanctioned nations or how it knows what their ethnicity is. A PhD student from Vancouver, Canada said he received the ban despite having no Slack contacts in Iran.

"Slack closed my account today! I'm a PhD student in Canada with no teammates from Iran! Is Slack shutting down accounts of those ethnically associated with Iran?! And what's their source of info on my ethnicity?" he tweeted.

A company representative told The Verge, that the deactivations were a result of an upgrade to Slack's geolocation system.

"We updated our system for applying geolocation information, which relies on IP addresses, and that led to the deactivations for accounts tied to embargoed countries," the representative said. "We only utilize IP addresses to take these actions. We do not possess information about nationality or the ethnicity of our users.

"If users think we've made a mistake in blocking their access, please reach out to and we'll review as soon as possible."

The team at SlackHQ did eventually get back to Omidi, but as yet have not resolved his issue: "Still no response at all and its the end of the workday in eastern US. I am surprised how long it takes them to reverse a ban or to issue some sort of statement on this," he tweeted.

Bobby Hellard

Bobby Hellard is ITPro's Reviews Editor and has worked on CloudPro and ChannelPro since 2018. In his time at ITPro, Bobby has covered stories for all the major technology companies, such as Apple, Microsoft, Amazon and Facebook, and regularly attends industry-leading events such as AWS Re:Invent and Google Cloud Next.

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