I have two different Facebook accounts with two different passwords and two distinct online personalities, one as myself and one as someone else. Since the last one week, to my horror, both accounts were fused as one. Has this happened to anyone else? How does Facebook decide to merge accounts?

Edit: I wanted to clarify my situation.

I have two Facebook accounts A and B, both using distinct email addresses. One is me posting as myself and the other uses a fictitious name.

I log out of A and log into B. I am logged into B now but I can access all of A's private messages. How is this even possible?

Furthermore when I log into B and post on A's wall saying, "This is terrible" then my message appears on A's wall as follows -

A > B This is terrible. In other words, Facebook conveys that this is A posting as B. Something is wrong.

closed as off topic by Jeff Ferland, AviD Apr 8 '12 at 9:34

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    In what way were they "fused as one"? More details would be helpful. Which name was kept? Which photos? Which friends list? When you log in as one, does it bring you to the other's page? Which FB Profile ID was kept? Etc. – Mark Beadles Apr 4 '12 at 16:46
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    How is this even remotely linked to security? – Lucas Kauffman Apr 4 '12 at 16:57
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    @LucasKauffman, it is related in that it relates to whether one can (in practice) establish and use pseudonyms on Facebook. Pseudonymity (and anonymity) are in scope for this site, I think. – D.W. Apr 4 '12 at 17:49
  • When you log in as one, it brings you to the other's page. I have seen this happen. – user8927 Apr 4 '12 at 17:52
  • @D.W. If that's so, then the OP should really change the title of this question. But, I'm not sure that we have enough info to go on. – schroeder Apr 4 '12 at 18:13

If what you are seeing is as some other folks said - when you try to log into one account, it actually logs you into your other account - then this may not be a server-side merge but a client-side login/logout issue. The scenario is fairly common and not limited to Facebook (similar things can happen with other Identity systems like OpenID or Shibboleth):

  1. Log in to Facebook as IdentityA. Facebook caches some stuff in a browser cookie.
  2. Do some stuff. Third-party apps might open Facebook sessions to "like" things.
  3. Log out of Facebook. Facebook logs you out but cookie isn't cleared, and/or third party apps retain their FB connections .
  4. Log in to Facebook as IndentityB. Facebook sees your existing session info (either from cookie or third-party connection) and uses it, logging you back into IdentityA.

If this is what's going on, a solution might be to close/reopen the whole browser, or to Ctrl-F5 clear cookies. Facebook isn't actually merging accounts, according to all available evidence.


Facebook wants to sell your information to advertisers and using fake names/demographic information is against their interests. Facebook specifically forbids pseudonyms for non-verified celebrity accounts. Facebook can probably determine to high accuracy if you have multiple accounts or are using a pseudonym from you and your friends' online behavior. They could see you tend to login from the set of IP addresses/computers (home, work/school, phone) at similar times but the accounts aren't linked, don't have related names, etc. Or there are never photos of person X. Or facebook determined "Awesome FancyPants" is not likely a real name. Or someone on facebook once messaged someone else saying something to the effect of "Awesome McFancyPants is John Doe's fake name." Or they've cross-referenced with other records and find no mention of anyone in NY State with the name Awesome McFancyPants.

Facebook will analyze user behavior to detect things not specifically told to them. For example, they will determine if you are engaged, even if you have not listed that as a your relationship status to better sell you to targetted advertisers (e.g., by analyzing comments in posted photos). Secret behavior tracking is not unique to facebook, e.g., Target will analyzer credit card users shopping habits to guess pregnancies for targetted fliers.

Facebook also tries out new features/algorithms on small subsets of users (e.g, 10% of users in Nevada), so this merging of fake accounts could be a new feature.

Or it could be an artifact of you or facebook not fully logging you out of your accounts.

  • I think your last sentence is the correct one. It doesn't seem like they are merged since he can see B's wall from A and vice versa. – Mark Beadles Apr 6 '12 at 15:13

Log into one account. Log off. Then log into your second account. If you see yourself still logged into the first account or see yourself as active on chat, FB's system might merge both accounts accidentally. So if you are posting as X, you may find yourself posting as Y and all X's friends will know you are Y and all Y's friends will know you are X. This is probably because Facebook's system knows both X and Y are the same person and in their system X and Y show up as one person's account based on the IP address. Sometimes there is a glitch in their system and that "outs" you.

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    They had better not merge people by IP address. It's not unusual at all for a number of people to share an IP address due to the use of things like proxies. – David Schwartz Apr 4 '12 at 20:38
  • This is more likely due to your browser caching your account. – Mark Beadles Apr 5 '12 at 17:40

This is amazing! I have never heard of this even know I have more than one account myself. The only way I could see this happening if you had similar photos and personalities online; however, you both are coming from the same IP.

Facebook even says on their website they don't offer to merge accounts:

Merging Facebook Accounts:


The only weird things I have heard from Facebook would include:

  • Forcing the Timeline (new layout)
  • Changing Privacy settings (phone number posted)
  • Random Glitches (everyone faces)
  • Logged out and forced to change password because they said I was hacked
  • They offer HTTPS to fight session highjacking, however don't make it default

Please let me know if this helps!

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