The 19 biggest U.S. banks must no later than today submit their plans to return capital to shareholders as part of a yearly Fed-supervised exercise that tests whether they have enough capital to keep lending during a severe economic downturn, reports the Wall Street Journal. Citigroup (C) will seek permission for its first share buyback since 2007 as part of the latest "stress tests," sources say. J.P. Morgan Chase's (JPM) plan is expected to call for a dividend rise and a share repurchase, sources say. Morgan Stanley (MS) isn't expected to ask for a dividend or buyback, and will hope to win Fed approval to complete a plan to take full ownership of a wealth-management unit this year. Fifth Third Bancorp (FITB) had its capital request rejected by the Fed last year, and is expected to ask for a dividend increase or buyback.