Apparently, there originally was something like 60 cents backing each $1 of tether. Then bitifinex needed the money to cover its legitimate business, so they swapped the tether dollars with an equal amount of dollars in a frozen bank account. And the account was frozen because the _bank_ it was deposited in has had all its accounts frozen by numerous investigating governments. After the swap, Bitfinix then had to be loaned $900 million to back tether, with shares in its business as collateral.

Sketchy is a generous characterization of tether. Tether is fraudulent.

https://www.bloomberg.com/opinion/articles/2019-04-26/things...