Determinants of Merger and Acquisition Success: A Comparative Study of the Failed Zee–Sony Merger and the Formation of JioStar

Mergers and acquisitions (M&A) are important corporate strategies used by businesses to expand market presence, acquire capabilities, achieve economies of scale and strengthen competitive advantage. However, the existence of strategic synergy between two companies does not necessarily guarantee the successful completion or integration of a merger. This research examines the determinants of M&A success through a comparative analysis of two major transactions in the Indian media and entertainment industry: the proposed merger between Zee Entertainment Enterprises Limited and Sony Pictures Networks India, which was terminated in January 2024, and the combination of Reliance Industries’ Viacom18 and The Walt Disney Company’s Star India businesses, which was completed in November 2024 and subsequently created JioStar. The study uses a qualitative comparative case-study approach based on academic literature, company announcements, regulatory information, financial reports and established financial journalism. The cases are analysed across six variables: strategic complementarity, financial preparedness, leadership and corporate governance, regulatory management, fulfilment of transaction conditions and post-merger integration. The findings indicate that both transactions possessed substantial strategic potential. The difference was primarily in execution. Zee–Sony experienced unresolved financial and contractual conditions, leadership uncertainty and governance concerns that prevented completion despite obtaining significant regulatory approvals. The Reliance–Disney combination established clearer ownership and leadership structures, committed fresh growth capital, responded to antitrust concerns through regulatory concessions and rapidly integrated important digital and sports assets following completion. The paper concludes that M&A success should be understood as a multi-stage process involving agreement, regulatory approval, transaction completion, operational integration and sustainable value creation. JioStar has successfully completed the first four stages and has demonstrated encouraging early operating indicators, although its long-term financial success remains too recent to determine conclusively.