No, NIMSPro3™ is not Open Source. NIMSPro3™ is proprietary software offered with a proprietary license that must be accepted to use the software.
The legacy NIMSPro™ 1.x was originally released by FutureFD under Open Source licensing terms, and it will continue to be offered under the original Open Source licensing.
NIMSPro3™ is completely new technology from the ground up, and it does not reuse any of the original NIMSPro™ 1.x source. NIMSPro3™ represents several years of development and a huge investment of resources and money by C3 Pathways.