Indian stock markets saw notable movements on August 18-20, 2025, driven by government policy changes and corporate developments. Shares of Maruti Suzuki, Hyundai Motor India, Mahindra & Mahindra, and Ashok Leyland reached record highs amid expectations of a Goods and Services Tax (GST) rate cut on small cars to 18%, which analysts say could fuel a consumption-led rally in the auto sector. Morgan Stanley highlighted Maruti, Ashok Leyland, and Mahindra & Mahindra as well positioned to benefit from the proposed GST reforms. Meanwhile, textile stocks such as Vardhman Textiles and Ambika Cotton surged up to 9% following the government's removal of an 11% import duty on cotton, boosting volumes at these counters. Ola Electric Mobility Ltd shares gained over 8% in a day and surged 23% over two days due to increased trading volumes. Godfrey Phillips India shares climbed more than 17%, reaching new highs despite concerns over a potential 40% 'sin tax'. In the pharmaceutical sector, Aurobindo Pharma emerged as the frontrunner to acquire Prague-based drugmaker Zentiva from private equity firm Advent International in a deal valued up to $5.5 billion, which could become the largest acquisition by an Indian pharmaceutical company. However, Aurobindo Pharma clarified that no binding agreement or definitive decision has been made yet. Hyundai Motor Group announced initiatives to advance software-defined vehicles (SDV) through collaborations and expanded its Los Angeles office. Vedanta shares experienced volatility after the Supreme Court rejected a plea related to additional compensation and amid government objections to a demerger plan. Muthoot Finance’s microfinance arm began offering gold loans following eased Reserve Bank of India norms. Chalet Hotels reported strong growth in the second quarter with expectations for momentum during the festive season. Overall, these developments reflect sector-specific responses to regulatory changes and strategic corporate actions in India's equity markets.