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We occasionally have to ask for a "Contributor License Agreement" from someone who sends in a patch or code that we want to include in the SpamAssassin codebase. This is a legal requirement (a similar situation applies in other projects, such as other ASF projects or the Linux kernel). It doesn't apply in all cases, just for "big" patches.
The \[http://www.apache.org/foundation/ ASF\] uses a form called the "Contributor License Agreement" for this. This can be found here: http://www.apache.org/licenses/#clas Wiki Markup
it's now possible to file CLAs via email:
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