CME GROUP INC. | 2013 | FY | 3


REDEEMABLE NON-CONTROLLING INTEREST
The following summarizes the changes in redeemable non-controlling interest for the years presented. Non-controlling interests that do not contain redemption features are presented in the statements of equity.
(in millions)
 
2013
 
2012
 
2011
Balance at January 1
 
$
80.8

 
$
70.3

 
$
68.1

Allocation of stock-based compensation
 

 

 
0.1

Total comprehensive income attributable to redeemable non-controlling interest
 
1.5

 
10.5

 
2.1

Purchase of non-controlling interest
 
(82.3
)
 

 

Balance at December 31
 
$

 
$
80.8

 
$
70.3


In April 2013, the company purchased the remaining 10% non-controlling interest in its business venture with Dow Jones for $80.0 million. Prior to the purchase, the company maintained a 24.4% interest in S&P/DJI. As a result of the purchase of the non-controlling interest, the company's interest in S&P/DJI increased to 27%. The company recognized a $165.6 million tax benefit through additional paid-in capital. The tax benefit was due to a reduction in deferred tax liabilities related to the tax basis in Index Holdings. The company also recognized a $2.3 million gain through additional paid-in capital related to the purchase of the non-controlling interest.

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