Cook County Circuit Judge William Maki ruled on July 8 that the Chicago Board Options Exchange (CBOE) would continue to have exclusive licenses on its index options products.

The battle goes back to 2006 when the International Securities Exchange (ISE) moved to list stock index options on the S&P 500 (SPX) and Dow Jones Industrial Average (DJX), both of which CBOE held exclusive licenses to list.

The court ruling prohibits ISE from listing or offering a market for trading in options on either index and forbids the Options Clearing Corporation (OCC) from clearing SPX and DJX options unless they were traded in accordance to CBOE’s exclusive license.

In the hearing ISE had argued the value of these indexes was found in the public domain and as such any exchange should be able to offer them. CBOE argued they were a product they had developed and licensed and as such should retain their exclusive license.

ISE plans to appeal the decision.