The Chicago-based trading desk said revenue has grown by 30 times, year over year.
FalconX is among the "white glove" crypto startups eager to cater to an institutional base.
FalconX announced Wednesday that American Express Ventures made the investment as an extension of a fundraise earlier this year, but did not disclose an amount.
The crypto trading firm pitched investors on the basis that its best trade execution platform offers institutions a solution to the wash trading that is rife in the space.