Commerce One Leading E-Commerce Solutions Available on Sun Solaris 8 Platform.

Business Editors/Technology Writers

PLEASANTON, Calif.--(BUSINESS WIRE)--June 27, 2001

Delivering on its commitment to offer Commerce One e-marketplace solutions on Sun's Solaris 8 Operating Environment ("OE"), the leading Internet platform, Commerce One, Inc. (Nasdaq:CMRC) today announced general availability of its e-marketplace products for Solaris OE. These products include MarketSite(TM), the e-marketplace operating environment, and Net Market Maker(TM), an e-marketplace solution for small and medium enterprises and e-marketplaces. In addition, MarketSet(TM) and Enterprise Buyer(TM), solutions jointly developed with SAPMarkets, Inc., will be used on the Sun platform by ForestExpress, a leading e-marketplace for the forest products industry. These products are all based upon open industry standards.

"Commerce One helps Global 1000 companies save money and increase sales on the Internet by bringing their customers and suppliers online to collaboratively conduct business," said Dennis Jones, chief operating officer and vice chairman of the board at Commerce One. "By working with Sun, Commerce One will expand its market to include the Sun installed base and give companies the ability to deploy highly scalable e-marketplaces that can support billions of dollars in transactions and services."

This extensive collaboration between Commerce One and Sun delivers on several joint engineering projects between the companies and includes the use of Java(TM) technology and components of the iPlanet platform.

About Commerce One

Commerce One (Nasdaq:CMRC) is the e-marketplace company. Through its software, services and Global Trading Web(TM) of interconnected business communities, Commerce One enables worldwide commerce on the Internet. With headquarters in Pleasanton, California and offices around the world, Commerce One can be reached by phone at 800/308-3838 or 925/520-6000 or via the Internet at www.commerceone.com.

Forward Looking Statements

The foregoing paragraphs include forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. These forward-looking statements include statements concerning the expected expansion of Commerce One's market base to include companies operating on Sun's Solaris 8 platform and the ability of Commerce One to provide e-marketplace solutions that enable companies to increase sales and reduce costs. The words "believe," "will" and similar phrases as they relate to Commerce One are intended to identify such forward-looking statements. Such statements reflect the current views and assumptions of Commerce One and are subject to various risks and uncertainties that could cause actual results to differ materially from expectations. These risks include, but are not limited to, reduction in demand for services and products exchanged on e-marketplaces, the continued cooperation of the parties, unexpected expenses, the possibility that e-marketplace services and solutions offered may not meet user expectations, the extent of customer adoption and utilization of the solutions provided, risks related to the Internet, general economic conditions, intense and increasing competition in the market and volatility of the stock market. For a discussion of these and other risk factors that could affect Commerce One's business, see "Risk Factors" in Commerce One's filings with the Securities and Exchange Commission, including its Annual Report on Form 10-K for the year ended December 31, 2000 as well as its Quarterly Report on Form 10-Q for the quarter ended March 31, 2001.

Copyright(c)2001. Commerce One, Many Markets. One Source. Global Trading Web, Commerce One.net, BuySite, MarketSite, eLink, MarketWise, Net Market Maker, XML Common Business Library, XML Development Kit, XML Commerce Connector, MarketSite Builder, and SupplyOrder are either trademarks or registered trademarks of Commerce One, Inc. Enterprise Buyer and MarketSet are trademarks of Commerce One, Inc., and SAPMarkets. All other company, product, and brand names are trademarks of their respective owners.

Note to Editors: Sun, Sun Microsystems, the Sun logo, Solaris, Java, iPlanet and The Network Is The Computer are trademarks or registered trademarks in the United States and other countries.