eDiscovery Daily Blog

Problems and Solutions for Slack Discovery

The Discoverability of Slack

As people turned to remote work in 2020, collaboration apps became a prevalent form of communication. Slack was so popular that some considered it to be the “new email.” Though some legal teams refute its discoverability, the FRCP intentionally established a broad definition of ESI to accommodate new data types. From corporate files to humorous GIFS and standard channel messages, Slack is a medium for large quantities of information. Thus, the application fits the requirements for discoverable digital evidence.[1] Accessing and producing that information, however, can present several challenges.

Production Problems

  1. Hundreds of Slack messages are sent every day.

Medium and large-scale corporations with active Slack users easily send over 100,000 Slack messages per month. Additionally, Slack generates a new file per day for each channel. Examinations of big data are slow and expensive. By proactively identifying specific channels to preserve, litigants can reduce production costs and time.[2]

  1. Slack is only one of many hosts for decentralized communications.

Nowadays, a single conversation can span multiple platforms. For example, if an employee asks their boss a question through email, they may hold a Zoom meeting to discuss it. After the Zoom meeting, they might use Slack to address any follow-up questions. Since the conversation was spread out, the snippet captured on Slack will lack the full context.

  1. Deciphering Slack exports can be difficult.

Slack messages are exported through JSON files, a format that’s a bit hard to understand. Additionally, the files don’t visually display media such as emojis and GIFS. In response to this problem, legal teams may opt to use screenshots as an alternative production method. However, the application only allows users to view and sort through the most recent 10,000 messages.[3]

Tips to Keep in Mind

  • Educate your employees or legal team about Slack’s retention policies.
  • If possible, consider upgrading to Slack’s premium version so that there is no message history limit.
  • Find an eDiscovery solution that will export Slack data in a thorough and understandable format.
  • Avoid preserving unneeded data by identifying which channels are more important than others.[4]


[1] Peter Callaghan, “Is Slack Content Discoverable? Yes It (Definitely) Is,” Pagefreezer, https://blog.pagefreezer.com/slack-content-is-discoverable

[2] Matthew Verga, “Discovery from Slack: It’s Complicated,” Xact Data Discovery, June 19, 2020, https://xactdatadiscovery.com/articles/discovery-from-slack-its-complicated/

[3] James Murphy, “The Shark in the Wave: Revealing the Lurking Danger of Slack Data,” Corporate Compliance Insights, June 17, 2019, https://www.corporatecomplianceinsights.com/the-shark-in-the-wave-revealing-the-lurking-danger-of-slack-data/

[4] James Murphy, “The Shark in the Wave: Revealing the Lurking Danger of Slack Data.”