Decision 37 ~ G.R. No. 224469 , changes to the land may be possible. These uses must also be reconciled with the ongoing communal nature of the IPs or ICCs' attachment to the land. 88 Professor (now Justice) Leonen, a highly esteemed scholar in constitutional law and the law on land and natural resources, shares this understanding about the foregoing limitations to the sui generis IP title. He underscores this limitation by highlighting the indigenous concept of ownership as expressed in Section 5 of IPRA that "ancestral domains and all resources found therein shall serve as the material bases of [the IPs'] cultural integrity," and not generally for exploitative purposes, and that ancestral domains including sustainable traditional resource rights are the IP' s private but community property which belongs to all generations and therefore cannot be sold, disposed or destroyed. 89 He stressed that IPRA introduced a new package of ownership rights distinct from those under civil law. Subject to this limitation, IP title entitles the right to choose the uses to which the land is put and to enjoy its economic fruits. 90 This IP concept of ownership is based on customary law and traced its origin to time immemorial "native title." Section 5 of IPRA strengthened these customary practices by emphasizing that ancestral lands and domains are the ICCs' and IPs' "private but community property which belongs to all generations." Section 56 of the IPRA even recognized the IPs' vested rights based on their existing property regime. With the passage of IPRA, formal recognition of the IPs' "native title" was attributed to their ancestral lands and domains. A Certificate of Ancestral Domain Title (CADT) may now be issued by the NCIP to ICCs and IPs. v. Reconciling IP rights to preserve cultural integrity and claim or title to ancestral domains and lands with the State's jura regalia and police power The State's jurd regalia is affirmed in Article XII, Section 2, of the Constitution: All lands of the public domain, waters, minerals, coal, petroleum, and other mineral oils, all forces of potential energy, fisheries, forests or timber, wildlife, flora and fauna, and other natural resources are owned by the State. With the exception of agricultural lands, all other natural resources shall not be alienated. The exploration, development, and utilization of natural resources shall be under the full control and supervision of the State. The State may directly undertake such activities, or it may enter into co-production, joint venture, or production-sharing agreements with Filipino citizens, or corporations or associations at least sixty per centum of whose capital is owned by such citizens. Such ss Jd. Prof. Mario Victor "Marvic" F, Leonen, "The Indigenous Peoples' Rights Act: An Overview of its Contents," PHILJA Judicial Journal (2002). 90 Supra note 8.3. 89