Clarent Corporation Files for Common Stock Offering.

REDWOOD CITY, Calif.--(BUSINESS WIRE)--Nov. 1, 1999--

Clarent(TM) Corporation (Nasdaq:CLRN) today announced that it has filed a Registration Statement on Form S-1 with the Securities and Exchange Commission.

The registration statement covers a proposed offering of up to 4,000,000 shares of common stock and includes 1,162,500 shares of common stock to be sold by selling stockholders. To the extent the underwriters sell more than 4,000,000 shares of common stock, the underwriters have an option to purchase up to an additional 600,000 shares, of which 512,500 shares shall be from Clarent Corporation and 87,500 shares shall be from certain selling stockholders.

This press release shall not constitute an offer to sell or the solicitation of an offer to buy nor shall there be any sale of these securities in any state in which such offer, solicitation, or sale would be unlawful prior to registration or qualification under the securities laws of any such state. The offer is made only by the prospectus, a copy of which may be obtained from Credit Suisse First Boston Corporation, Eleven Madison Ave., Attn: Prospectus Department, New York, NY 10010-3629 or at 212/325-2580.

Forward-Looking Statements

This press release contains forward-looking statements. Such statements reflect management's current expectations. However, actual results could vary dramatically as a result of known and unknown risks and uncertainties, including but not limited to potential issues relating to the company's ability to maintain gross margins, ability to retain key customers, inability to expand sales and channels, risks associated with international business, lengthy sales cycles, and other known or unknown risks and uncertainties. For a more detailed description of these and other risks and uncertainties affecting the company's performance, see the company's prospectus filed pursuant to Rule 424(b) of the Securities Act of 1933, with the Securities and Exchange Commission on July 1, 1999 and to the Periodic Reports on Forms 10Q filed most recently with the SEC on Aug. 16, 1999. Clarent assumes no obligation to update the forward-looking information contained in this press release.

About Clarent Corporation

Clarent Corporation is a premier provider of scaleable, IP telephony products to carriers and Internet service providers around the world. Clarent's intelligent architecture and the Clarent Command Center enable Clarent products to route, manage, inter-connect and terminate high volumes of calls for service provider customers including some of the world's largest long distance telecommunication companies. According to a Cape Saffron report published in 1999, more minutes travel across Clarent-enabled networks worldwide than those of any other equipment supplier.(1)

Founded in July 1996, Clarent is publicly traded on Nasdaq under the symbol CLRN. The company is headquartered in Redwood City and has offices in major cities in Asia, Europe, Latin America and North America.

Note to Editors: Clarent is a registered trademark of Clarent Corporation in the United States and other jurisdictions. All other company or product names mentioned may be trademarks or registered trademarks of the respective companies with which they are associated.

(1) Cape Saffron "Global IP Voice/Fax Market 1999." Cape Saffron is an UK-based research group focused on the international voice market.