Slack, the workplace messaging platform owned by Salesforce, has restricted third-party software firms from searching or storing user messages, according to a report by The Information published Tuesday.

The move marks a significant shift in how external applications can interact with Slack’s data via its application programming interface.

The decision stems from recent updates to Slack’s terms of service, which were quietly rolled out in late May.

“As AI raises critical considerations around how customer data is handled, we’re committed to delivering AI and data services in a way that’s thoughtful and transparent,” the spokesperson said.

Salesforce emphasized that it is “reinforcing safeguards around how data accessed via Slack APIs can be stored, used, and shared,” amid growing concerns over data privacy and the use of enterprise information in AI training models.

APIs enable external applications to communicate and exchange data with platforms like Slack. However, under the new rules, apps such as Glean—which previously allowed companies to integrate Slack messages into internal search tools or knowledge graphs—can no longer index or retain that data long-term.

In an email to customers cited by The Information, Glean warned that the restrictions would limit users’ ability to incorporate Slack content into enterprise AI tools, calling it a setback for customers trying to maximize the utility of their own data.

The move comes as AI developers face increasing scrutiny over how personal and enterprise data is accessed and utilized in the training and operation of advanced AI systems. By tightening access to Slack messages, Salesforce aims to strike a balance between AI innovation and stricter data governance.