A gift to a stranger is revocable any time so long as the subject of the gift exists. It is not allowed when:
It perishes or is transformed
There is a substantial change in it or has increased in value
Third party interest is created
A gift to parents, a blood relative and souses cannot be retracted after delivery of possession has been made.
Successors in interest of donor cannot revoke gift after his death.
A gift cannot be revoked when done is dead and subject matter of the gift has devolved upon his legal heirs.
