(MKS LOGO) EXHIBIT 99.1 FOR IMMEDIATE RELEASE Contact: Ron Weigner Vice President and Chief Financial Officer 978.284.4446 MKS INSTRUMENTS REPORTS FIRST QUARTER 2005 RESULTS Wilmington, Mass. -- April 26, 2005 -- MKS Instruments, Inc. (NASDAQ: MKSI), a leading worldwide provider of process control technologies for improving productivity in semiconductor and other advanced manufacturing processes, today reported first quarter 2005 financial results that exceeded revenue and earnings guidance given on February 10, 2005. Net sales were $127.4 million, down 4.2 percent from $133.0 million in the first quarter of 2004 and down 2.6 percent from $130.9 million in the fourth quarter of 2004. GAAP net earnings were $5.5 million, or $0.10 per diluted share, compared to $12.7 million, or $0.23 per diluted share, in the first quarter of 2004. Fourth quarter 2004 GAAP net earnings of $24.1 million, or $0.44 per diluted share, included a non-cash adjustment to reverse a previously established valuation allowance against net deferred tax assets. Excluding this adjustment, fourth quarter 2004 net earnings were $7.4 million, or $0.14 per diluted share. Non-GAAP earnings, which exclude amortization of acquired intangible assets and special items, were $8.0 million, or $0.15 per diluted share, compared to $16.8 million, or $0.31 per diluted share in the first quarter of 2004, and $11.1 million, or $0.20 per diluted share, in the fourth quarter of 2004. "Our sales and earnings exceeded our guidance, and gross margin improved in the first quarter," said John Bertucci, Chairman and Chief Executive Officer. "We continued to develop products that enhance the performance and productivity of process tools, and to work with semiconductor customers on next generation opportunities. We continued to have success at the leading edge, where utilization rates are higher. We are participating in many customer evaluations of our products, including subsystems that integrate multiple technologies, and I am pleased with our success. "Looking ahead, based on current customer order patterns, second quarter 2005 sales could remain essentially flat and range from $124 to $129 million. GAAP net earnings could range from $0.10 to $0.13 per diluted share, and non-GAAP earnings could range from $0.14 to $0.17 per diluted share. Our visibility is limited because of our short lead times, making it difficult to estimate business levels beyond the current quarter. However, we tend to reflect broad industry trends, because we provide a range of solutions to semiconductor OEMs and fabs, and our process monitoring and control products are on most front-end processes. Based on some recently published industry spending forecasts and surveys, we are cautiously optimistic about the outlook for the balance of this year." The financial results that exclude certain charges and special items are not in accordance with Accounting Principles Generally Accepted in the United States of America (GAAP). MKS has historically been acquisitive, and MKS' management believes the presentation of non-GAAP financial measures, which exclude the costs associated with acquisitions and other special items, is useful to investors for comparing prior periods and analyzing ongoing business trends and operating results. Management will discuss first quarter financial results on a conference call today at 5:00 p.m. (Eastern Daylight Time). A live web cast and replay of the conference call will be available at www.mksinstruments.com in the "Investors" section. To hear a telephone replay through May 3, 2005, dial 303-590-3000, pass code 11027307#. MKS Instruments, Inc. is a leading worldwide provider of process control solutions for advanced manufacturing processes such as semiconductor device manufacturing; thin-film manufacturing for flat panel displays, data storage media, architectural glass and electro-optical products; and technology for medical imaging equipment. Our instruments, components and subsystems incorporate sophisticated technologies to power, measure, control, and monitor increasingly complex gas-related semiconductor manufacturing processes, thereby enhancing our customers' uptime, yield and throughput, and improving their productivity and return on invested capital. This release contains projections or other forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995 regarding MKS' future growth and the future financial performance of MKS. These projections or statements are only predictions. Actual events or results may differ materially from those in the projections or other forward-looking statements set forth herein. Among the important factors that could cause actual events to differ materially from those in the projections or other forward-looking statements are the fluctuations in capital spending in the semiconductor industry, fluctuations in net sales to MKS' major customers, potential fluctuations in quarterly results, the challenges, risks and costs involved with integrating the operations of MKS and any acquired companies, dependence on new product development, rapid technological and market change, acquisition strategy, manufacturing and sourcing risks, volatility of stock price, international operations, financial risk management, and future growth subject to risks. Readers are referred to MKS' filings with the Securities and Exchange Commission, including its most recent Annual Report on Form 10-K, for a discussion of these and other important risk factors concerning MKS and its operations. MKS is under no obligation to, and expressly disclaims any obligation to, update or alter its forward-looking statements, whether as a result of new information, future events or otherwise. ### MKS INSTRUMENTS, INC. UNAUDITED CONSOLIDATED STATEMENTS OF OPERATIONS (IN THOUSANDS, EXCEPT PER SHARE DATA) Three Months Ended ------------------------------------------ March 31, March 31, December 31, 2005 2004 2004 --------- --------- ------------ Net sales $ 127,407 $ 132,985 $ 130,859 Cost of sales 78,045 78,756 82,716 --------- --------- --------- Gross profit 49,362 54,229 48,143 Research and development 14,549 14,336 13,816 Selling, general and administrative 23,849 20,152 21,500 Amortization of acquired intangible assets 3,690 3,693 3,691 Restructuring charges 454 437 -- --------- --------- --------- Income from operations 6,820 15,611 9,136 Interest income, net 1,098 272 873 --------- --------- --------- Income before income taxes 7,918 15,883 10,009 Provision (benefit) for income taxes 2,460 3,177 (14,106) --------- --------- --------- Net income $ 5,458 $ 12,706 $ 24,115 ========= ========= ========= Net income per share: Basic $ 0.10 $ 0.24 $ 0.45 Diluted $ 0.10 $ 0.23 $ 0.44 Weighted average shares outstanding: Basic 53,878 53,255 53,680 Diluted 54,393 55,085 54,272 THE FOLLOWING SUPPLEMENTAL NON-GAAP EARNINGS INFORMATION IS PRESENTED TO AID IN UNDERSTANDING MKS'S OPERATING RESULTS: GAAP net income $ 5,458 $ 12,706 $ 24,115 Adjustments (net of tax): Amortization of acquired intangible assets 2,306 3,693 3,691 Restructuring charges 272 437 -- Benefit for income taxes (NOTE 1) -- -- (16,729) --------- --------- --------- Non-GAAP net income (NOTE 2) $ 8,036 $ 16,836 $ 11,077 ========= ========= ========= Non-GAAP net income per share (NOTE 2) $ 0.15 $ 0.31 $ 0.20 Weighted average shares outstanding - diluted 54,393 55,085 54,272 NOTE 1: The three month period ended December 31, 2004 includes a benefit of $16,729 for the reversal of the previously established valuation allowance against net deferred tax assets. NOTE 2: The Non-GAAP net income and non-GAAP net income per share amounts exclude amortization of acquired intangible assets, acquisition and disposition related charges and special items, net of applicable income taxes. MKS INSTRUMENTS, INC. UNAUDITED CONSOLIDATED BALANCE SHEET (IN THOUSANDS) March 31, December 31, 2005 2004 ---- ---- ASSETS Cash and short-term investments $244,917 $235,900 Trade accounts receivable 82,770 82,315 Inventories 97,663 99,633 Other current assets 21,986 22,037 -------- -------- Total current assets 447,336 439,885 Property, plant and equipment, net 80,197 80,917 Long-term investments 2,597 4,775 Goodwill 256,114 255,740 Other acquired intangible assets 37,806 41,604 Other assets 5,382 5,756 -------- -------- Total assets $829,432 $828,677 ======== ======== LIABILITIES AND STOCKHOLDERS' EQUITY Short-term debt $ 21,802 $ 24,509 Accounts payable 26,283 23,338 Accrued expenses and other liabilities 39,180 44,338 -------- -------- Total current liabilities 87,265 92,185 Long-term debt 6,690 6,667 Other long-term liabilities 3,621 3,191 Stockholders' equity: Common stock 113 113 Additional paid-in capital 632,808 631,760 Retained earnings 87,535 82,077 Other stockholders' equity 11,400 12,684 -------- -------- Total stockholders' equity 731,856 726,634 -------- -------- Total liabilities and stockholders' equity $829,432 $828,677 ======== ========