Facebook said it investigated the complaints, initially from members in France, and was satisfied there had been no breach of privacy.
"A small number of users raised concerns after what they mistakenly believed to be private messages appeared on their Timeline," the California-based social network said in an email response to an AFP inquiry.
"Our engineers investigated these reports and found that the messages were older wall posts that had always been visible on the users' profile pages."
Concerns that private Facebook messages from 2007, 2008, or 2009 were being posted for public viewing spread wildly on one-to-many text message service Twitter after a story first appeared in free French daily Metro.
Facebook remained adamant that messages at issue were "wall" posts that have always been open to viewing by others and not made with private side-conversation tools subsequently added to the service.
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