necessary for the customary activities of the employer. A work created under Rwandan Government initiative for official purposes shall belong to the Rwandan State, unless provided otherwise in a contract. Article 227: Ownership of audiovisual work The original owners of the moral and economic rights shall be the co-authors of the audiovisual work, as the director, the author of the scenario or the composer of the music. The authors of pre-existing works included in, or adapted for, the making of the audiovisual work shall be assimilated to the co-authors of the audiovisual work. The conclusion of a contract under which the co-authors of an audiovisual work undertake to make contributions to the audiovisual work shall, unless provided otherwise in the said contracts, imply a presumption of the assignment to the producer of the audiovisual work of the economic rights on their contributions. This presumption shall not apply to musical works. Notwithstanding provisions of paragraph two (2) of this article, the co-authors shall, however, maintain their economic rights in their contributions to the extent that those contributions can be subject of acts covered by their economic rights separately from the common audiovisual work, unless provided otherwise in the said contracts. SECTION 5: ASSIGNMENT RIGHTS Article 228: Assignment of moral rights The moral rights shall not be transmissible during the life of the author, but the right to exercise any of those rights shall be transmissible by testamentary disposition or by operation of law on succession. Article 229: Assignment of economic rights The economic rights are personal property and are transmissible by testamentary disposition or by operation of law on succession. During the period of protection the right owner may assign, by contract arrangement, these rights, in whole or in part, to third person or legal entity. The assignment contract shall be valid only if it is made in writing and signed by parties to the contract. Article 230: Assignment contract of economic rights The assignment contract of economic rights on the work to carry out any act of economic rights use shall be limited to certain acts and specific kind of use or include certain restrictions to the plan of purposes, the aim of use, the duration of use, the scope and territorial extend and the means of use.