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SpamAssassin is an Apache Software Foundation project and is released under the Apache License. The Apache Software Foundation provides organizational, legal, and financial support for a broad range of open source software projects. As a US 501(c)(3) public charity, the Foundation provides an established framework for contributions of both intellectual property and funding for the support of open source software development. Through a collaborative and meritocratic development process, Apache projects deliver enterprise-grade, freely available software products for the public benefit, attracting large communities of users and enabling future innovation, both commercial and individual, through its pragmatic Apache License.