Perthi S. Josan's career trajectory took another significant turn in 2005 when he became the Managing Director of Advancemas Sdn Bhd., a company involved in the trading of petroleum products. Under his leadership, Advancemas became a trading partner of renowned companies like Petronas, Petroleum Authority of Thailand, Shell Eastern Trading Corporation, Emirates National Oil Company, and TNB Fuel, showcasing his ability to navigate the complexities of the energy sector. In 2006, Perthi S. Josan expanded his business interests further by investing in a plant manufacturing biodegradable plastic resin and biodegradable plastic disposable bags, where he was responsible for overseeing operations, procurement, and sales.

Perthi S. Josan's entrepreneurial journey continued to evolve, as he expanded his business activities in 2010 to include coal and iron production, mining, and trading in Indonesia. By 2016, he had diversified his portfolio to include shipping operations for crude oil and fuel oil commodities, demonstrating his ability to seamlessly integrate various aspects of the supply chain. Throughout his extensive career, Perthi S. Josan has demonstrated a strong commitment to continuous learning and professional development. He holds a Bachelor of Science degree in Chemistry from the University of Malaya and has obtained various certifications in areas ranging from Shipping Documentation, Procedures and Incoterms to Coal Commodity Uses in Industries and Trade Finance Facilities.

Perthi S. Josan's success can be attributed to his in-depth technical knowledge, strategic leadership, and unwavering commitment to innovation and operational excellence. His ability to navigate and excel in diverse industries, from chemicals to energy and beyond, is a testament to his versatility and adaptability as a business leader.