The concept of patrimony can have various meanings depending on the assets and their purpose Existential patrimony, which refers to certain assets, has a community, family, or humanitarian purpose, and is essential for the preservation of life family and humanity. Balancing rights and duties concerning existential patrimony is a challenging task. Measures will be proposed to protect the family’s existential patrimony during and after death. The project also aims to analyze strategies implemented and/or to be implemented for the conservation of humanity’s existential patrimony, particularly the natural patrimony. Keywords: Existential patrimony; Family patrimony; Natural and universal patrimony; Collective patrimony; Tutelage.