Chicago Exchanges End Merger Negotiations

The Chicago Board Options Exchange, the largest U.S. options market, said Thursday that it has ended talks with the Chicago Board of Trade about a possible merger.

The negotiations were called off late Wednesday just hours before CBOT Holdings Inc., the parent of the Chicago Board of Trade -- the second-largest U.S. futures exchange -- sued the options exchange over membership rights, the options exchange said.

“Although exploratory discussions with other exchanges have taken place in the past, and may take place in the future, CBOE is not currently in discussions with any other parties regarding these types of transactions,” the options exchange said.

A Chicago Board of Trade spokeswoman declined to comment. Shares of CBOT Holdings fell 3%, or $3.86, to $112.75 before the news was announced.