Bill Gates is once again the world's richest person.

The 57-year-old co-founder of Redmond, Washington-based Microsoft Corp recaptured the title from Mexican investor Carlos Slim on Thursday, according to the Bloomberg Billionaires Index, as the software maker hit a five-year high. It is the first time Gates has held the mantle since 2007. His fortune is valued at US$72.7 billion, up 16 percent year-to-date.

Slim's America Movil SAB, the largest mobile-phone operator in the Americas, has dropped 14 percent this year after Mexico's Congress passed a bill that could quash the billionaire's market dominance.

Microsoft shares have surged 28 percent this year, buoyed by cost controls and sales of business and server software amid weak demand for personal computers running the new Windows 8 operating system.

Berkshire Hathaway Inc Chairman Warren Buffett is the world's third-richest person with US$59.7 billion, according to the Bloomberg ranking. He is US$3.7 billion ahead of Spaniard Amancio Ortega, Europe's wealthiest person.

Ingvar Kamprad, the founder of IKEA, ranks fifth with a US$55.6 billion fortune.