Competition between bitcoin and cryptocurrency exchanges is heating up as millions of new users flock to crypto following huge price rises this year.

The bitcoin price, after soaring to around $65,000 per bitcoin in April, has fallen sharply but the likes of San Francisco-based Coinbase continue to make millions in transaction fees.

Now, Jack Mallers, the chief executive of Chicago-based bitcoin payments company Strike, has warned that Coinbase is not “competing in the free market”—announcing Strike will let U.S. customers buy and sell bitcoin for almost no fees.

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