ISE Intl Secs Exchange Hldgs

The International Securities Exchange (NYSE:ISE) said today that Citadel Derivatives Group LLC, will serve as bin 4 Primary Market Maker (PMM) as of June 3, 2005. Citadel Derivatives Group LLC purchased the bin 4 Primary Market Maker (PMM) from Adirondack Electronic Markets LLC. Citadel serves as bin 8 PMM and as CMM in eight bins. The firm also has Electronic Access Member (EAM) privileges to route orders to ISE for execution. "Citadel's name has come to represent sophisticated electronic trading and high-quality markets and we are pleased that the company has chosen to maintain two PMMs at ISE," said Gary Katz, ISE's Chief Operating Officer. Adirondack Electronic Markets currently serves as a PMM in bin 3 and as a Competitive Market Maker (CMM) in bins 1, 2, 5, 6 and 10. Adirondack Electronic Markets began trading in bin 4 in October 2003. ISE lists more than 700 different options classes, representing about 90% of options industry volume. ISE's market is divided into ten bins, with one PMM and up to 16 CMMs in each bin. Since ISE's launch on May 26, 2000, the exchange's low-cost, high-efficiency business model has attracted a new class of participants to the options market whose embrace of electronic trading has fundamentally changed the nature of US options trading. Most PMMs and CMMs are operated by large, global financial institutions with significant capital base and notable trading experience. ISE Background The International Securities Exchange, the world's largest equity options exchange, was founded on the principle that technology fosters and infuses new efficiencies and operational innovations into securities trading. After developing an innovative market structure that integrated auction market principles into an advanced screen-based trading system, ISE launched the first fully electronic US options exchange in May 2000. ISE continually enhances its trading systems to provide investors with the best marketplace to execute their options orders. For more information about ISE, its products and its technology, visit www.iseoptions.com.