https://www.helpnetsecurity.com/2008/09/19/tumbleweed-files-patent-infringement-suit-against-sendmail-inc/
Tumbleweed files patent infringement suit against Sendmail, Inc - Help Net Security
Sep 19, 2008 - Tumbleweed Communications Corp., a wholly owned subsidiary of Axway Inc. announced it has filed a patent infringement suit against Sendmail, Inc. in
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