Exhibit 99.1

FOR IMMEDIATE RELEASE

CYMER REPORTS FIRST QUARTER 2012 OPERATING RESULTS

SAN DIEGO, Calif., April 24, 2012 - Cymer, Inc. (Nasdaq: CYMI), the world’s leading supplier of light sources used by chipmakers to manufacture advanced semiconductor devices, today announced operating results for the first quarter ended March 31, 2012.

For the first quarter of 2012:

Commenting on results, Bob Akins, Cymer’s chief executive officer, said, “First quarter revenue exceeded our expectations as we received customer acceptance on the remaining three extreme ultraviolet (EUV) 3100 sources. We believe this pull-forward of acceptance is another acknowledgement of our continued progress towards successful EUV development. Our deep ultraviolet (DUV) light source competitiveness remained strong and we continued to demonstrate high responsiveness to favorable changes in customer demand. DUV pulse utilization, while seasonally lower in January, began to rise in February as anticipated and increased throughout March. As a result, OnPulse revenue remained strong driven by the mix of higher value ArF pulses and installed base growth. In the first quarter, we also recognized two tax benefits which resulted in a favorable tax rate.”

In the first quarter of 2012, the company shipped 26 DUV light sources, of which 17 were ArF immersion and 9 were KrF, and the company installed 47 DUV light sources at chipmaker locations. Gross profit was $75.5 million for the first quarter of 2012, yielding a 50.2 percent gross margin. Total operating expenses, which include research and development and selling and administrative expenses, were $58.8 million. Total operating income was $16.7 million or 11.1 percent of revenue. A tax benefit related to a foreign subsidiary and an agreement with the Internal Revenue Service to close out a prior period tax audit benefited the company’s first quarter effective tax rate. The first quarter effective tax provision was a benefit of $4.8 million.

DUV and Installed Base Products (IBP) bookings for the first quarter of 2012 totaled $135.8 million, resulting in a book-to-bill ratio of 1.06. Sixty-nine percent of the DUV bookings were ArF immersion, 28 percent were KrF, and three percent were ArF Dry. The company ended the quarter with a DUV backlog of approximately $56.2 million.

As of March 31, 2012, cash and investments totaled approximately $348 million.

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Company Outlook

Commenting on the outlook for the second quarter of 2012, Akins stated, “We have demonstrated technology feasibility of our EUV source utilizing prepulse, and our confidence has grown in its power scalability. We are aggressively accelerating commercialization of the initial production 3300 sources which requires a significant increase in our EUV RD&E investment. This investment is in direct support of growing industry demand and fulfillment of our 3300 source order from ASML for production ready EUV lithography tools. In the second quarter, we expect Installed Base Products revenue to rise driven primarily by higher DUV pulse utilization, increased ArF pulses, OnPulse enhancements, and installed base growth. We anticipate shipping a slightly higher number of DUV light sources as compared to the first quarter. We also expect to recognize revenue on two TCZ crystallization tools.”

Based on information available at this time, Cymer is providing the following guidance for the second quarter of 2012:

Cymer’s management will hold a conference call at 2:00 pm (PDT) today, April 24, 2012, to discuss first quarter operating results and second quarter 2012 guidance. This press release, the conference call and accompanying slides may be accessed on the investor relations page of the company’s Web site at www.cymer.com.

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Forward Looking Statements

Statements in this press release that are not strictly historical in nature are forward-looking statements. These statements include, but are not limited to statements regarding the development and performance of the company’s EUV source technology, the company’s development of and manufacturing capability for its silicon crystallization tool for the display industry, expectations for DUV pulses and growth in Installed Base Products revenue, and the statements under the caption “Company Outlook” above. These statements are predictions based on current information and expectations and involve a number of risks and uncertainties. In addition, statements regarding backlog and book-to-bill ratios should not be read as predictions or projections of future performance. Actual events or results may differ materially from those projected in any of such statements due to various factors, including but not limited to: the risk that the company’s EUV sources, which are still under development and not capable of supporting the commercial production of integrated circuits, may not meet customer specifications or may have reliability or performance problems; the risk that commercial EUV systems may not be introduced by the company on time, or at all; the risk that a competitor’s EUV or other source may be selected over the company’s EUV source; the demand for semiconductors in general, and, in particular, for leading-edge devices with smaller geometries; cyclicality in the market for semiconductor manufacturing equipment; the timing of customer orders, shipments and acceptances; delays or cancellations by customers of their orders; the performance and market acceptance of the company’s new products or technologies; new and enhanced product offerings by competitors; the company’s ability to meet its production and product development schedules; the rate at which semiconductor manufacturers adopt new technologies and purchase and take delivery of photolithography tools from the company’s customers; the company’s ability to secure adequate supplies of critical components for its advanced products; the company’s ability to manage its expense levels and unanticipated expenses; the company’s ability to achieve its forecasted gross margin which includes its ability to absorb manufacturing costs; the company’s ability to align its cost structure with forecasted business levels; the company’s ability to manage its foreign currency exposure; the performance and conditions in the United States and world financial markets; the policies and actions of the United States and other governments; and general economic conditions. For a discussion of these and other factors which may cause our actual events or results to differ from those projected, please refer to the company’s most recent annual report on Form 10-K and quarterly reports on Form 10-Q, as well as other subsequent filings with the Securities and Exchange Commission (SEC). You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date of this press release. All forward-looking statements are qualified in their entirety by this cautionary statement, and the company undertakes no obligation to revise or update any forward-looking statements to reflect events or circumstances after the date of this press release.

About Cymer

Cymer, Inc. (Nasdaq: CYMI) is the market leader in developing light sources, used by chipmakers worldwide to pattern advanced semiconductor chips, and is pioneering a new silicon crystallization tool for the display industry. Cymer’s light sources have been widely adopted by the world’s top chipmakers and the company’s installed base comprises approximately 3,750 systems. Continuing its legacy of leadership, Cymer is currently pioneering the industry’s transition to EUV lithography, the next viable step on the technology roadmap for the creation of smaller, faster chips. The company is headquartered in San Diego, Calif., and supports its customers from numerous offices around the globe. Cymer maintains a Web site to which it regularly posts press releases, SEC filings, and additional information about Cymer. Interested persons can also subscribe to automated e-mail alerts or RSS feeds. Please visit www.cymer.com.

Cymer and all other Cymer product or service names used herein are either registered trademarks or trademarks of Cymer, Inc. Any other marks mentioned herein are the property of their respective holders.

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CYMER, INC.

CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED)

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CYMER, INC.

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CYMER, INC.

CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)

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