Facebook has reacted to the latest round of hoax posts about privacy settings, saying life on Mars is now more likely than the introduction of charges for a private profile setting.
Rumours about Facebook's privacy settings have resurfaced on the social network and been shared thousands of times.
One claimed that the firm planned to charge £5.99 to keep profiles private.
Facebook moved quickly to quash the rumour.
In a light-hearted post, it said: "While there may be water on Mars, don't believe everything you read on the internet today. Facebook is free and it always will be. And the thing about copying and pasting a legal notice is just a hoax. Stay safe out there Earthlings."
The two posts have been in circulation for several years but in recent days have taken on a new momentum, being shared thousands of times in users' timelines.
The first hoax post reads: "Now it's official! It has been published in the media. Facebook has just released the entry price: £5.99 to keep the subscription of your status to be set to "private". If you paste this message on your page, it will be offered free (I said paste not share) if not tomorrow, all your posts can become public. Even the messages that have been deleted or the photos not allowed. After all, it does not cost anything for a simple copy and paste. (Not worth risking it!)
Another hoax, purporting to be a legally binding statement reads: "As of September 28th, 2015 at 10:50 pm, I do not give Facebook or any entities associated with Facebook permission to use my pictures, information, or posts, both past and future. By this statement, I give notice to Facebook it is strictly forbidden to disclose, copy, distribute, or take any other action against me based on this profile and/or its contents.
"The content of this profile is private and confidential information... NOTE: Facebook is now a public entity. All members must post a note like this.
"If you prefer, you can copy and paste this version. If you do not publish a statement at least once it will be tactically allowing the use of your photos, as well as the information contained in the profile status updates."
Its privacy policies can be perplexing for some users.
As security blog NakedSecurity puts it: "Facebook may pull some weird stunts, but making its users' posts public unless they fork over some moolah or paste a particular status message? Um, no.
"If the company up and decided to take our privacy, douse it with lighter fluid and then toss in a lit match - all without any notice whatsoever - but with the completely unheralded option of snatching it from the fire with a random bunch of sentences pasted into your status update, you'd have heard about it," it added.