ISE Second Market Experiences Rapid Growth in First Month of Trading.

Improved Market Quality Contributes to Overall Volume Expansion in Second Market

NEW YORK -- The International Securities Exchange (NYSE: ISE) said today that average daily trading volume in its Second Market for options has grown to approximately 35,000 contracts since its launch on October 16, 2006. ISE introduced the Second Market to create tight markets and additional liquidity for options classes that have typically experienced lower trading volumes.

As a result of increased competition, Second Market symbols currently trade an aggregate of 55% more volume across all exchanges than in the three months prior to ISE listing these names. This volume growth reinforces ISE's belief that enhanced competition among exchanges improves market quality, which leads to greater trading interest. In the past, similar volume increases also occurred in equity, ETF, and certain index options when greater competition was introduced for these products.

David Krell, ISE's President and Chief Executive Officer, noted, "We are very pleased with the results of the first month of trading in ISE's Second Market. As we anticipated, overall market quality has improved and volumes have grown as a result of greater competition in these listings. We expect this trend to continue as more names are added to the Second Market in the coming weeks."

Currently, 260 symbols are traded in the Second Market. ISE plans additional listings and expects to include approximately 800 options classes in the Second Market by the end of January 2007. The Second Market offers separate quoting rules and access standards from ISE's primary market to provide greater flexibility for competitive market making. Citadel Derivatives Group LLC, Merrill Lynch Professional Clearing Corporation, Morgan Stanley & Co. Incorporated, SLK-Hull Derivatives LLC, Timber Hill LLC, and UBS Securities LLC act as Primary Market Makers (PMMs) in the Second Market. Additionally, ten firms currently participate as Competitive Market Makers (CMMs) in these listings.

ISE Background

International Securities Exchange Holdings, Inc. (NYSE: ISE), through its subsidiaries, operates a family of innovative securities markets. ISE is founded on the principle that technology and competition create better, more efficient markets for investors and consists of an options exchange, a stock exchange and an alternative markets platform. ISE continually enhances its trading systems and develops new products to provide investors with the best marketplace and investment tools to trade smarter.

ISE developed a unique market structure for advanced screen-based trading systems and in May 2000 launched the first fully-electronic US options exchange. Currently, ISE operates the largest U.S. equity options exchange and is among the leading options exchanges in the world. ISE offers index options, including a portfolio of proprietary index products, and enhanced market data products for sophisticated investors. ISE FX Options[TM] are slated to launch in 2007.

ISE Stock Exchange, launched in September 2006 with strategic partners, includes an innovative MidPoint Match[TM] platform which offers investors continuous price improvement. It is expected that MidPoint Match will be integrated with a fully-displayed Best Bid Offer market in the fourth quarter of 2006.

ISE's alternative markets business currently consists of an events market trading platform known as Longitude. Longitude's patented and proprietary technology provides a unique parimutuel structure for derivatives auctions which results in greater trading and pricing flexibility for market participants.

For more information about ISE and its options exchange, visit www.iseoptions.com and for more information about ISE Stock Exchange, visit www.isestock.com. Additionally, to learn more about ISE alternative markets technology, visit www.longitude.com.

Forward Looking Statements

Certain matters discussed in this press release are "forward looking statements" intended to qualify for the safe harbor from liability established by the Private Securities Litigation Reform Act of 1995. These statements relate to future events or our future financial performance, and involve known and unknown risks, uncertainties and other factors that may cause our actual results, levels of activity, performance or achievements, to be materially different from those contemplated by the forward looking statements. We undertake no ongoing obligation, other than that imposed by law, to update these statements. Factors that could affect our results, levels of activity, performance or achievements and cause them to materially differ from those contained in the forward looking statements can be found in our filings with the Securities and Exchange Commission, including our annual report on Form 10-K, current reports on Form 8-K and quarterly reports on Form 10-Q, as amended.