Facebook says reports that private messages are being made public are not true.
Some Facebook users are adamantly insisting that private messages they sent to other members are now appearing on their timelines for others to see.
But Facebook says an investigation suggests that's not the case.
"A small number of users raised concerns after what they believed to be private messages appeared on their timeline. Our engineers investigated these reports and found that the messages were older wall posts that had always been visible on the users' profile pages," reads a statement.
"Facebook is satisfied that there has been no breach of user privacy."
Facebook is estimated to have more than 900 million users worldwide, including about 18 million in Canada.
Canada's privacy commissioner Jennifer Stoddart has criticized Facebook in the past for not doing enough to let users control their personal information online.
A spokeswoman said Monday that her office is looking into the user complaints.
"If it's true it would indeed be troubling (but) ... we don't yet know for sure what's happening," said Anne-Marie Hayden.
"We are currently looking into it although we haven't launched a formal investigation. We do plan to speak with Facebook's Canadian representatives to ask what's happening from their point of view and we're going to continue to monitor the situation very closely."