Mastercard is trading 6.7% higher at $588.74 in after-hours trading amid Open Standard’s launch of OUSD, a dollar-pegged stablecoin backed by Mastercard and other major companies; reports have not explicitly attributed the move to the launch. - Mastercard-owned BVNK is among OUSD’s initial access providers. - Partners committed more than $1 billion in launch liquidity. - Mastercard closed September 30, 2026, at $551.59; the Nasdaq rose 0.28%, while the S&P 500 and Dow declined.