U.S. Patent & Trademark Office Grants Tumbleweed A New Digital Certificate Patent

Redwood City, CA – July 5, 2006 -- Tumbleweed® Communications Corp. (NASDAQ:TMWD), a leading provider of email security, managed file transfer, and identity validation appliance and software products, today announced that it has been granted U.S. Patent No. 7,073,056 by the U.S. Patent and Trademark Office.

The new patent, titled "Apparatus and Method for Demonstrating and Confirming the Status of Digital Certificates and Other Data” describes a method and apparatus for demonstrating and confirming the status of digital certificates and other data. The new patent is a continuation of U.S. Patent No. 6,532,540, which is itself a divisional of Patent No. 5,903,651, the application for which was filed on May 14, 1996.

Tumbleweed's patent portfolio includes 23 granted U.S. utility patents. The patent portfolio broadly covers secure communication over Internet standards.

SAFE HARBOR STATEMENT
Tumbleweed cautions that forward-looking statements contained in this press release are based on plans and expectations as of the date of the press release, and that a number of factors could cause the actual results to differ materially from the guidance given at this time. These factors are described in the Safe Harbor statement below.

Except for the historical information contained herein, the matters discussed in this press release may constitute forward-looking statements that involve risks and uncertainties that could cause actual results to differ materially from those projected, particularly with respect to the development and enforcement of the Tumbleweed patent portfolio. In some cases, forward-looking statements can be identified by terminology such as “may,” “will,” “should,” “potential,” “continue,” “expects,” “anticipates,” “intends,” “plans,” “believes,” “estimates,” and similar expressions. For further cautions about the risks of investing in Tumbleweed, we refer you to the documents Tumbleweed files from time to time with the Securities and Exchange Commission, particularly Tumbleweed’s Form 10-K filed March 16, 2006 and Form 10-Q filed May 10, 2006.

Tumbleweed assumes no obligation to update information contained in this press release. Although this release may remain available on Tumbleweed’s website or elsewhere, its continued availability does not indicate that Tumbleweed is reaffirming or confirming any of the information contained herein.

About Tumbleweed Communications Corp.
Tumbleweed provides security solutions for email protection, file transfers, and identity validation that allow organizations to safely conduct business over the Internet. Tumbleweed offers these solutions in three comprehensive product suites: MailGate®, SecureTransport™ and Validation Authority™. MailGate provides protection against spam, viruses and attacks, and enables policy-based message filtering, encryption and routing. SecureTransport enables business to safely exchange large files and transactions without proprietary software. Validation Authority is the world-leading solution for determining the validity of digital certificates. Tumbleweed’s enterprise and government customers include ABN Amro, Bank of America Securities, Catholic Healthcare West, JP Morgan Chase & Co., The Regence Group (Blue Cross/Blue Shield), St. Luke's Episcopal Healthcare System, the US Food and Drug Administration, the US Department of Defense, and all four branches of the US Armed Forces. Tumbleweed was founded in 1993 and is headquartered in Redwood City, Calif. For additional information about Tumbleweed go to www.tumbleweed.com or call 650-216-2000.

Tumbleweed, MailGate, SecureTransport, and Validation Authority are either registered trademarks or trademarks of Tumbleweed Communications Corp. in the United States and/or other countries. All other trademarks are the property their respective owners.

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