A hacktivist group called NullBulge leaked data from almost 10,000 of Disney’s Slack channels in July.

The entertainment company reportedly issued a memo to staff that a migration away from Slack’s collaboration application will conclude next year. The move follows a high-profile data breach that led to the publication of 44 million Slack messages and tens of thousands of documents by a hacking group.

Disney told employees on Thursday that it will no longer use Slack for internal communication after a hack earlier this year allowed cybercriminals to expose financial materials, computer codes, and o