If you have any expectations about the privacy of your Skype communications, you may want to reassess them.

Microsoft appears to be peeking into Skype messages for security reasons, according to Ars Technica.

The owner of Skype regularly scans the contents of messages sent on the service for signs of fraud, but what’s done with the information from those scans—whether it’s stored indefinitely or destroyed—is unknown.

Similar findings were published by The H Security last week.

“Skype uses automated scanning within instant messages to identify unwanted messaging and identify website addresses that have been previously flagged as spam, fraud, or phishing links,” Skype spokesperson James Blamey said in an email statement.

However, H Security maintained that Microsoft appears to be leaving HTTP URLs untouched while scanning HTTPS URLS. HTTPS URLS are typically linked to secure websites and not spam sites.

The discovery by Ars and independent security researcher Ashkan Soltani raises questions about the privacy of communications on Skype.