The IoT SDK consists of two different license terms for its SDK and SoftDevice components. Please read and understand the terms of use for each of the components.
All IoT SDK components excepting the SoftDevice and the third party libraries use the license terms specified here.
The SoftDevice used for the IoT SDK is a technology prototype only. Read the license agreement at <InstallFolder>components/softdevice/s1xx_iot/s1xx-iot-prototype3_licence_agreement.pdf before you use the SoftDevice.
Nordic's IoT SDK includes two third party components.
lwIP uses BSD 3.0 license. The license can be found here.
mbedTLS uses Apache 2.0 license. The license can be found here.