Harvard Business School Alumni Association Honors Siebel Systems with 2003 Entrepreneurial Company of the Year Award

Business Wire, May 30, 2003

1998

-- "Fastest-growing company in Silicon Valley," San Francisco

Chronicle

-- Ranked 20th among Northern California corporations, The Los

Angeles Times

1997

-- Ranked seventh in Los Angeles Times 100, The Los Angeles Times

-- Named one of a dozen companies from the "Software 500" deemed

noteworthy in their market segments, Software Magazine

About HBSA/NC

The HBSA/NC is one of the oldest of all Harvard Business School alumni associations, and with more than 1,000 active members it also one of the largest. The HBSA/NC allows members to stay in contact with fellow alumni, further their professional training, and participate in community partners programs.

About Siebel Systems

Siebel Systems, Inc. is a leading provider of eBusiness applications software, enabling corporations to sell to, market to, and serve customers across multiple channels and lines of business. With more than 3,500 customers worldwide, Siebel Systems provides organizations with a proven set of industry-specific best practices, CRM applications, and business processes, empowering them to consistently deliver superior customer experiences and establish more profitable customer relationships. Siebel Systems' sales and service facilities are located in more than 28 countries.

Except for the historical information contained herein, this press release contains forward-looking statements that involve risk or uncertainties. Future operating results of Siebel Systems may differ from the results discussed or forecasted in the forward-looking statements due to factors that include, but are not limited to, risks associated with customer relations, such as the availability of Siebel Systems' products and services, customer implementation of products and services, relationships with customers, third-party vendors and systems integrators, concentration of revenues in a relatively small number of customers, existence of errors or defects in products, ability to successfully manage growth, significant current and expected additional competition and the need to continue to expand product distribution and services offerings. Further information on potential factors that could affect the financial results of Siebel Systems are included in Siebel Systems' Annual Report on Form 10-K, Quarterly Reports on Form 10-Q and its other filings with the Securities and Exchange Commission, which are available at www.sec.gov. Siebel Systems assumes no obligation to update the information in this press release.

Note to Editors: Siebel is a trademark of Siebel Systems, Inc. and may be registered in certain jurisdictions. All other product and company names mentioned are the property of their respective owners and are mentioned for identification purposes only.

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