Washington, Sep 22 (IANS): Two Indian Institute of Technology alumni have made it to Forbes' list of the 400 richest Americans topped for the 18th year in a row by Bill Gates with Warren Buffett second.

While Microsoft co-founder Gates' fortune swelled by $5 billion in a year to $59 billion, according to the US business magazine, Bharat Desai with $1.35 billion gets the 329th spot with Vinod Khosla two notches below at 331st place with $1.3 billion.

Kenya born Syntel co-founder Desai, 58, an IIT, Bombay graduate founded the outsourcing outfit in 1980, took the company public in 1997 and now has some 16,200 employees. Shares have jumped 20 percent over the past year.

Fellow IITian Vinod Khosla, 56, according to Forbes "is the rare Silicon Valley venture capitalist able to generate profits from a clean tech portfolio."

The Indian-born engineer, who made his early fortune as a cofounder of Sun Microsystems, recently vowed to give away half his fortune to charity when he signed Bill Gates' and Warren Buffett's Giving Pledge last April.

The Berkshire Hathaway Inc. chairman and CEO Buffett's fortune decreased by $6 billion - the largest dollar-amount loss by anyone on the Forbes 400 this year, to $39 billion, the magazine said.

He was the only person among the top 20 on Forbes' list to see his fortune shrink from a year ago.

Oracle CEO Larry Ellison rounds out the top three richest Americans with a net worth of $33 billion, $6 billion more than last year.

Facebook founder Mark Zuckerberg was the biggest dollar gainer on the list, with a net worth of $17.5 billion that earned him the No. 14 spot.

Forbes said the combined wealth of the 400 people, including 42 women, on this year's list is $1.5 trillion, with an average net worth of $3.8 billion, up 12 percent from last year.