Comment 4 for bug 28477

If we want to be as specific as we can (recalling Scott's remark on IRC):

"To merge two Launchpad accounts, you must be logged in on Launchpad under the account you want to keep, and have access to the e-mail address registered under the duplicated account. Once you’ve proven that you own the duplicated account's e-mail address, it will be assigned to you, along with everything else owned by the duplicated account."