Section 2. Rules of Interpretation. In the interpretation of the provisions of the Act and these rules, the following shall apply: a) All doubts in the interpretation of the provisions of the Act, including its these rules, or any ambiguity in their application shall be resolved in favor of the ICCs/IPs. b) In applying the provisions of the Act in relation to other national laws, the integrity of the ancestral domains, culture, values, practices, institutions, customary laws and traditions of the ICCs/IPs shall be considered and given due regard. c) The primacy of customary laws shall be upheld in resolving disputes involving ICCs/IPs. d) Customary laws, traditions and practices of the ICCs/IPs of the land where the conflict arises shall first be applied with respect to property rights, claims and ownership, hereditary succession and settlement of land disputes. e) Communal rights under the Act shall not be construed as co-ownership as defined in Republic Act No. 386, otherwise known as the New Civil Code of the Philippines; f) In the resolution of controversies arising under the Act, where no legal provisions or jurisprudence apply, the customs and traditions of the concerned ICCs/IPs shall be resorted to; and g) The interpretation and construction of any of the provisions of the Act shall not in any manner adversely affect the rights and benefits of the ICCs/IPs under other conventions, international treaties and instruments, national laws, awards, customary laws and agreements. Section 3. Appeals to the Court of Appeals. Decisions of the NCIP is appealable to the Court of Appeals by way of a petition for review within fifteen (15) days from receipt of a copy thereof. Section 4. Execution of Decisions, Awards, and Orders. Upon expiration of the period herein provided and no appeal is perfected by any of the contending parties, the Hearing Officer of the NCIP, on its own initiative or upon motion by the prevailing party, shall issue a writ of execution requiring the sheriff or the proper officer to execute final decisions, orders or awards of the Regional Hearing Officer of the NCIP. Section 5. Jurisdiction and Quasi-judicial Functions of the NCIP. In relation to its quasi-judicial powers, the NCIP shall : a) Through its regional offices, have jurisdiction over all claims and disputes involving the rights of ICCs/IPs; b) Promulgate rules and regulations governing the hearing and disposition of cases filed before it as well as those pertaining to its internal functions and such rules and regulations as may be necessary to carry out the purposes of the Act; c) To administer oaths, summon the parties to a controversy, issue subpoenas requiring the attendance and testimony of witnesses or the production of such books, papers, contracts, records, agreements and other documents of similar nature as may be material to a just determination of the matter under investigation or hearing conducted in pursuance of the Act; d) To hold any person in contempt, directly or indirectly, and impose appropriate penalties therefor; and e) To enjoin any or all acts involving or arising from any case pending before it which, if not restrained forthwith, may cause grave and irreparable damage to any of the parties to the case or seriously affect social or economic activity. Section 6. No Restraining Order or Preliminary Injunction. No inferior court of the Philippines shall have jurisdiction to issue any restraining order or writ of preliminary Page 50