Tumbleweed has licensed its patents to 29 companies, including the following:

• American Greetings Corporation, Inc.
• BorderWare Technologies, Inc.
• CipherTrust Inc.
• Critical Path, Inc.
• CyberGuard Corporation
• DST Systems, Inc.
• eBay, Inc.
• Entrust, Inc.
• Hallmark Cards, Incorporated
• Intermix Media, Inc.
• IronPort Systems, Inc
• Kana Software, Inc.
• Mirapoint, Inc.
• NetIQ Corporation
• New River, Inc.
• Proofpoint, Inc.
• Secure Data in Motion, d/b/a Sigaba Corporation
• Sendmail, Inc.
• Ticketmaster
• Vircom, Inc.
• Yahoo, Inc.
• Zix Corporation