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This page is a list of some, in all likelihood a very small fraction actually, of the sites out there that use Apache Tomcat in production. For security and other policy-related reasons, many organizations choose not to disclose the server they use. Tomcat has been downloaded more than 10 million times: assuming even a 1% production adoption rate results in more than 100000 installations. As an aside for the curious, you can see recent Tomcat download statistics on Vadim Gritsenko's page / Technische Übersetzung, Übersetzung Niederländisch Deutsch. Note, however, that these represent downloads from apache.org servers only, and not from mirrors, so they are likely to represent only a small minority of downloads: the total number is much (more than an order of magnitude) greater. Companies that support Tomcat, such as SpringSource claim more than half of the global Fortune 500 as their clients.
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