$BTC Shares of Visa and Mastercard fell on Friday after the Wall Street Journal reported that Walmart and Amazon.com, among other merchants, were considering issuing their own stablecoins to customers, a move that could siphon revenue from traditional payment providers.

The Journal said that merchants' decisions on whether to disclose stablecoins—cryptocurrencies pegged to stablecoins like the US dollar—depend on the passage of the Genius Act, a bill moving through Congress that would regulate currencies and require issuers to hold reserves of dollars or other liquid assets.