Here is the announcement they made:
Today is a bittersweet day. This month we turned nine years old; and while I am excited and proud that we’ve come this far, I am also very sad. Today, Bittrex is beginning the process of winding down its U.S. operations. Don’t worry – all customer funds are safe and available to withdraw; however, it’s just not economically viable for us to continue to operate in the current U.S. regulatory and economic environment.
...Nine years later, the crypto ecosystem is very different. Regulatory requirements are often unclear and enforced without appropriate discussion or input, resulting in an uneven competitive landscape.
In the end, we made great strides toward accomplishing our goal of maturing the crypto space. However, operating in the U.S. is no longer feasible and Bill, Rami and I will focus on helping Bittrex Global succeed outside the U.S.
So Operation Chokepoint 2.0 takes another scalp.
This will have an impact on Hive, as Bittrex US was one of the few exchanges Americans could buy and sell Hive on.
I guess people can trade on Ionomy. But my prediction is that Hive will start to get swapped for Litecoin on Hive-engine, which then enables people to send the Litecoin to Coinbase or other exchanges still clinging on in the USA.
My other thought was that hive-engine needs to keep as low a profile as possible in order to avoid Operation Chokepoint. They can't come after you if they don't know you exist.