CHICAGO (CBS) — The parent company of the Chicago Mercantile Exchange and Board of Trade is the latest firm to threaten to move out of Illinois over the corporate income tax increase earlier this year.

As WBBM Newsradio 780’s Nancy Harty reports, Terrance Duffy, chairman of the CME Group, said company officials are looking at opportunities elsewhere, but no decision has been made.

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CME group chief financial officer James Parisi says Illinois’ tax hike in January to 9.5 percent from 7.3 percent cost the company an extra $50 million a year.

LISTEN: Newsradio 780’s Nancy Harty reports

Duffy tells the Chicago Sun-Times he is upset by the state’s failure to close corporate tax loopholes. He accuses the state of favoring some companies, but leaving others, including CME, to pay the full rate.

CME owns the Chicago Mercantile Exchange, the Chicago Board of Trade and the New York Mercantile Exchange. The firm was created after the Mercantile Exchange bought out the Board of Trade for $11.9 billion in 2007.

Duffy said CME could retain some operations in Illinois if it relocated.

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The CME Group is the latest in a slew of companies that have threatened to leave the state over the tax hike.

Peoria-based Caterpillar made headlines in March for a letter indicating that it might leave the state, but chief executive officer Doug Oberhelman decided to keep the company in following a meeting with Gov. Pat Quinn.

Later, Quinn offered Motorola Mobility $100 million in financial incentives to keep its corporate headquarters in Libertyville.

Navistar and Sears, Roebuck & Co., have also reportedly considered moving out of Illinois over the tax hike.

Quinn supported a hike in corporate and personal income tax rates this year as a way to shore up the state’s historic budget deficits.

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