Joda-Money source code is released under the business-friendly Apache 2.0 license. This is the same license as all Apache Software Foundation projects.
As is normal with the Apache 2.0 license, a NOTICE file exists for Joda-Money:
============================================================================= = NOTICE file corresponding to section 4d of the Apache License Version 2.0 = ============================================================================= This product includes software developed by Joda.org (http://www.joda.org/).