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The mysterious name is an older "user" named @freedom

Noticed them on steemwhales.. holding #3 for quite some time, by a solid margin. They aren't new.

Okay I see the issue, the top richest users list above is ranked by Steem Dollars which is the liquid currency on the steem blockchain, @freedom only has $1.77 Steem Dollars in their account, and most of their wealth is held in Steem Power which is the metric used to determine voting power, but not a liquid currency. For your convenience here is the AskSteem list of top users ranked by Steem Power:

UsernameSteem Power
steemit70712504
freedom7183800
steem4913756.5
ned4436561
dan4160243.25
blocktrades2836369
val-a2543433.5
mottler2231285.25
abit1943398.25
databass1691378.125

Interesting. Thanks!