The U.S. Justice Department has filed an antitrust lawsuit against Visa, accusing the payment giant of illegally dominating the debit card market and contributing to inflated prices for a wide range of goods and services. This lawsuit, which follows reports of Visa stock dropping by 5% upon the announcement, claims that Visa's practices stifle innovation and lock out potential rivals. Recent trading activities raised eyebrows after it was revealed that Nancy Pelosi's husband sold over $500K in Visa stocks shortly before the lawsuit was filed. The outcome of this case could have significant implications for the payment industry and for Visa's market position.