Slack Technologies Inc, a corporate chatroom startup, has received inquiries about a potential takeover from technology companies, including Amazon.com Inc (AMZN.O), Bloomberg reported on Thursday.

A deal could value the company at at least US$9 billion, the report said, citing people with knowledge of the matter.

Slack declined to comment, while Amazon did not immediately respond to request for comment.

Slack is a platform where employees can send messages, collaborate, organize and share files.

The technology also integrates with a wide variety of business software - such as Salesforce.com Inc (CRM.N) and Microsoft Corp's (MSFT.O) Skype.

The San Francisco-based company has raised more than US$500 million from venture capitalists and was valued at $3.8 billion at its last private financing round a year ago.