Microsoft under the leadership of its India-born CEO Satya Nadella has overtaken oil giant Exxon Mobil to become the world's most valuable company after iPhone maker Apple Inc. Exxon Mobil Corp ceded its title after the five-month oil rout cut USD 47 billion from its market value. Nadella introduced drastic changes to restructure the company that has been struggling with the declining market in personal computers. The price of the tech giant's shares are up over 30 per cent over the year - the highest it has been for a decade. Investors have been pleased with Nadella's emphasis on web-based Cloud services, and his efforts to undo the mistakes of Windows 8. The company was also benefitted from Wall Street's approval of Nadella, BBC said. Under Nadella's lead, Microsoft now focuses on mobile technology and web-based cloud services and while cutting jobs and company expenses may have brought ire from those affected, Nadella's strategy appeared to have worked. Shares in Microsoft - which have been rising after a strong October earnings report - hit USD 49.81. That gives it a value of USD 410.5bn. The price of the tech giant's shares are up over 30 per cent over the year - the highest it has been for a decade. At the end of May, Microsoft is fourth on Forbes list of largest companies in the world based on market capitalisation but Nadella's effort is seen to have positively influenced the turnaround of the company, which has now overtaken Exxon Mobil that held the second spot earlier this year.