https://crypto-anonymous-2021.medium.com/the-bit-short-insid...

The last nail in the coffin was when I found out about the lack of visible reserves. If Tether Ltd. really was taking in 1 USD for each Tether it issued, then it should have as many dollars in its bank account as there are issued Tethers. And it turns out we can check if that’s true! Tether Ltd.’s bank is Deltec bank in the Bahamas, and the Bahamas discloses how much foreign currency its domestic banks hold each month.

The answer was — at least up to the end of September 2020 — not nearly enough:

From January 2020 to September 2020, the amount of all foreign currencies held by all the domestic banks in the Bahamas increases by only $600 million — going from $4.7B to $5.3B. (The table is in Bahamian dollars, but the Bahamian dollar is pegged to the US dollar, so 1 BSD = 1 USD.)

But during the same period, total issued Tethers increased by almost $5.4 billion — going from $4.6B to $10B!