* Taxes on dividends to rise unless Obama, Congress act
* Special dividend more than double prior annual dividend
By Ann Saphir
CHICAGO, Dec 5 (Reuters) - CME Group Inc, the biggest operator of U.S. futures exchanges, on Wednesday joined a number of companies moving 2013 dividend payouts to this month to shield shareholders from expected tax increases.
CME's board of directors approved a plan to pay a $1.30-per-share annual variable dividend this month, instead of next year as earlier planned. The payout is more than double the company's prior annual dividend.
"Because of uncertainty regarding future taxation of dividends, CME Group's board of directors has accelerated the timing of this dividend - which would have been paid in first-quarter 2013 - into the fourth quarter of 2012 in order to maximize the after-tax value to its shareholders," CME said in a statement.
More than a dozen other companies, including Wal-Mart Stores Inc., have moved 2013 dividend payments into December or declared special December dividends.
Without action from Congress in coming weeks, George W. Bush-era tax cuts on capital gains and dividends will expire at the end of 2012. The accelerated dividend payments allow shareholders to avoid higher tax rates in 2013, which for the wealthiest could double.
President Barack Obama and Republican lawmakers are at loggerheads over what to do about the tax increases and spending cuts -- known collectively as the "fiscal cliff" -- slated to take effect by Jan. 1 unless a deal is reached.
Obama insists on higher taxes for the top 2 percent, a stance Republicans in Congress show no signs of agreeing to. [ID: L1E8N54O8].
CME's annual variable dividend of $1.30 per share is payable on Dec. 28 to shareholders of record on Dec. 17, it said. It paid its first annual variable dividend in March 2012, of $0.60 per share.
CME also will pay a regular quarterly dividend of $0.45 per share on Dec. 26 to shareholders of record on Dec. 10. 2012.