Do we like them?

Do we like Slack?

Workplace messaging and collaboration software, based in San Francisco, owned by Salesforce.

Our score: 6 out of 10. A useful, widely used work tool with no regulator fines in our search. The AI data-wording row and the tighter API rules count against it, so we'd back it only with some caution.

Slack is the workplace chat app, now part of Salesforce. Our search turned up no regulator fines against it, which is a decent start for a company that holds a lot of private work conversations.

In 2024 a user spotted wording in Slack's privacy principles about analysing customer data to build AI and machine-learning models, and people were angry. Slack said its traditional ML models use de-identified, aggregate data and don't access message content. It later reworded the page.

In 2025 Salesforce changed the Slack API terms. Law firm Hunton says they now bar bulk exports, persistent copies or indexes, and use of the data in large language models. Salesforce can change those terms on notice. Some in the industry see it as a way to keep the data for Salesforce's own AI.

Overall it's a solid, mainstream product with no fines in our search, but the AI data rows and the tighter grip on customer data keep it in the middle of the table.