The data collection does not happen automatically. There is a several-step process for team owners to request access, which includes sending a signed letter on company letterhead to Slack stating that the company’s policies allow that kind of access. Each request is reviewed by Slack for approval, the company says.
Once granted, workers on the team are notified of the data access, which includes all messages from that point forward. The feature is not retroactive.
From: Slack: Be less busy.
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