All the ANT+ reference code (ANT+ simulator and ANT+ reference designs) is provided under the ANT+ Adopter Agreement. You will see the agreement when you register for access to the ANT+ Adopter Zone, and it is also available in the device profiles.
Specifically about the ANT Libraries (ANT Windows and Mac OS Library packages), we are moving towards an Apache 2.0 license, and will be clarifying this in our website and downloads in the future.
