Some crypto market observers believe Tether and related instruments are usually used in legitimate fashion and essential to robust digital currency markets.

“Bitfinex nor Tether is, or has ever, engaged in any sort of market or price manipulation. Tether issuances cannot be used to prop up the price of bitcoin or any other coin/token on Bitfinex,” said Bitfinex and Tether chief executive JL van der Velde in a statement to the Post.

In the U.S., some regulators and exchange operators are taking increased steps to spot and prevent manipulation in crypto markets.

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