Assessing the Validity of a Letter of Assignment as a Legal Basis for Cooperation Agreements in Indonesian Contract Law

A Case Study of Supreme Court Decision No. 4735 K/Pdt/2024

Abstract

Studies in Indonesian contract law have largely addressed the formal requirements of agreements under Article 1320 of the Civil Code; however, no jurisprudential study has specifically examined the substantive approach of the Supreme Court in recognizing work orders as contractual instruments. This study aims to analyze the legal validity of work orders (surat perintah) as the basis for cooperative agreements and the legal consequences of unilateral termination of such cooperation, with reference to Supreme Court Decision Number 4735 K/Pdt/2024. The research employs a normative legal method, combining a statutory approach (Civil Code), a case approach (Supreme Court Decision No. 4735 K/Pdt/2024), and a conceptual approach drawing on contract law doctrine. The study finds that a work order may acquire binding contractual force if it satisfies the four conditions of Article 1320 of the Civil Code, namely consent, legal capacity, a definite object, and a lawful cause. In the decision under examination, the Supreme Court assessed the actual performance of obligations, the existence of a reciprocal relationship, and the good faith of the parties as indicators of an implicit contractual relationship. Unilateral termination of such a relationship constitutes a breach of contract (wanprestasi) giving rise to an obligation to compensate the injured party. The novelty of this article lies in demonstrating that Indonesian Supreme Court jurisprudence is evolving toward a more substantive and responsive approach to contractual relationships, transcending mere documentary formality and thereby contributing to the development of modern contract law in Indonesia.