To help keep Battle.net accounts as secure as possible, we've recently changed how Battle.net authenticators can be used. Going forward, Battle.net authenticators can now only be associated with one Battle.net account at a time. No changes are being made to how many game licenses a single Battle.net account can support. You can still have multiple World of Warcraft accounts under a single Battle.net account, for instance, and all game licenses linked with a Battle.net account will still be protected if an authenticator is in use.
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