A cryptocurrency start-up has taken out a full-page ad in the Wall Street Journal to take a dig at JPMorgan Chase CEO Jamie Dimon, who recently called bitcoin a "fraud".

Switzerland-based start-up Eidoo launched Wednesday and bills itself as a digital wallet for people to hold ethereum, the second-largest cryptocurrency by market cap. It has plans to launch a debit card to spend both ethereum and bitcoin as well as an exchange to trade both.

The WSJ ad, which is a clear public relations stunt as the company launches, reads: "Maybe Jamie will fire you. But, you'll be free to trade in the crypto-world."

Eidoo is taking aim at Dimon's comments on bitcoin in which he called it a "fraud" and said that he'd "fire in a second" any JPMorgan trader who was trading bitcoin because "it's against our rules and they are stupid."