Snapchat has responded to the public outcry, explaining that this is simply not the case. But having spread around the world via mainstream media, the rumour may be hard to quash - perhaps the app's Ghostface Chillah mascot spooked people over Halloween.
In a separate blog post, the company confirmed that any messages "are automatically deleted from our servers once we detect that they have been viewed or have expired":
David Emm, Principle Security Researcher at Kaspersky Lab commented: "With the recent changes to Snapchat’s terms and conditions, the company has signaled its turn away from simply offering an app that gives people the possibility to secretly send pictures to friends.
"Snapchat is not the first company that has tried to find new means of income by selling pictures. Instagram, owned by Facebook, tried something similar, but subsequently reverted to their previous terms and conditions after the community pressure reached giant dimensions. Using Snapchat following the changes does not mean that your pictures will necessarily show up on the next advertisement board: but it may be a good idea to think about what could happen to your photos, because as a customer you do not have the possibility of tracking where, when and by whom your pictures are accessed and used.
"This can lead to a serious breach of your privacy. We would reiterate what we always say about pictures on the internet: think about what you are posting before you do so, because you may not have any control over what happens to those pics. Snapchat’s current change of T&Cs demonstrates that clearly."