U.S. operations of Deutsche Bank and Santander have again failed the Federal Reserve's stress test, leaving them unable to send cash back to their European parents and drawing a rebuke from regulators. The results leave Santander Holdings USA with the dubious honor of being the only lender to have failed the tests three years running, while Deutsche Bank Trust Corp tallied up its second failure in a row. Market support for the lenders was already fragile following Britain's decision to leave the EU and the two banks shares reacted predictably to the U.S.