Trimethylindium (TMIn) is the indispensable organometallic precursor that powers the world’s most advanced compound semiconductor manufacturing. As the primary indium source in metal-organic chemical vapor deposition (MOCVD), this highly specialized material enables the production of indium gallium nitride (InGaN), indium phosphide (InP), and indium gallium arsenide (InGaAs) — compound semiconductors that underpin LEDs, laser diodes, high-frequency electronics, solar cells, and emerging photonic technologies. For procurement professionals, supply chain strategists, and chemical distributors, understanding who buys trimethylindium and where demand concentrates is essential for navigating this tightly controlled and relationship-driven market. This guide maps the global buyer landscape, regional demand patterns, and the procurement dynamics that define the trimethylindium value chain.…