Nasdaq Inc. (NDAQ) has agreed to acquire Deutsche Borse’s International Securities Exchange in a $1.1 billion cash deal that will make the buyer the king of U.S. options trading, surpassing Chicago’s CBOE Holdings as market leader. The deal, announced late Wednesday, will give Nasdaq ownership of ISE’s three U.S. equity options exchanges - ISE, ISE Gemini and ISE Mercury. According to the buyer, these together handle more than 15% of U.S. options trading volume. Nasdaq, which already has three options exchanges of its own, will reportedly control nearly 40% of the US market after the combination. The takeover will also double Nasdaq’s stake in Options Clearing Corp. to 40%. Nasdaq, which reportedly had been eyeing ISE for a while, is projecting a minimum of $40 million in annualized expense synergies within 18 months of closing. Nasdaq has been on a spending spree as of late, recently adding the Chi-X Canada stock market and news release distributor Marketwired. Under the agreement, Deutsche Borse said that it will keep its ownership interests in Bats Global markets and Digital Asset Holdings. The buyer plans to fund the purchase through a combination of debt and cash on hand, but said it does expect to have a material impact on its financial leverage or capital return strategy.