If a fellow would like to change host organisation during the project s/he should contact the Project Officer in charge of the fellowship to provide guidance.
Generally, the MSC Individual Fellowships are not "portable" in the sense allowed under other schemes such as the ERC grants. However, it is possible to transfer the training activities to a new beneficiary, when there are serious reasons affecting the capacity of the host institution to implement the action (e.g. an internal reorganisation affecting the implementation of the action; dismantling of the research team involved in the action; departure of the supervisor from the beneficiary’s premises; serious conflict between the researcher and the supervisor).
Personal circumstances of the researcher (e.g. other professional opportunities, personal or family commitments) are NOT considered valid grounds for transferring the GA to a new beneficiary.
For more information see pages 470-471 of the Annotated Model Grant Agreement: