Rajat Gupta, Goldman Sachs' former Indian-American director convicted of insider trading, has received letters of support from the likes of Microsoft co-founder Bill Gates and former UN Secretary General Kofi Annan ahead of his sentencing .

Gates and Annan are among more than 200 friends of Gupta, 63, who have written letters to US District Judge Jed Rakoff through his lawyers ahead of the Oct 24 sentencing, according to local media reports.

"I know most personally that the poor of the world have a profoundly capable and articulate advocate in Rajat Gupta," wrote Gates, who worked with Gupta when the latter served as chair of the Global Fund to Fight AIDS, Tuberculosis and Malaria.

The Wall Street Journal citing submissions examined by it said Gates wrote that he was "not in a position to comment on any of the particulars of the case against him," but wanted to lend his voice "to round out Rajat's profile."

Annan, who was UN Secretary General from 1997-2006 said Gupta worked on many projects with him. "I came to respect his judgment, and we became good friends." On one of the projects, management reform at the UN, Gupta was an adviser.

Ajit Jain, a top Berkshire Hathaway executive and possible successor to Buffett, in his letter to the judge wrote that the impression of Gupta at his trial of someone who abused his position "for personal gain or aggrandizement" is "wholly inconsistent with the character of the man I know."

"On no occasion of our meetings did Rajat ever seek to inappropriately obtain or leverage information," he wrote, adding that Gupta "has already paid a terrible price" and "been disgraced personally and professionally."

Gupta's family also wrote to the judge, including his wife, four daughters and an 84-year-old aunt in India.

Gupta's submissions, according to the Journal, include letters from a class of luminaries not often seen at sentencing, but reflective of those he associated with as a top executive at McKinsey and through the philanthropic causes he supported.

Gupta was convicted in June of giving Sri-Lankan American hedge-fund manager Raj Rajaratnam inside information about Goldman's financial results and an investment by Berkshire Hathaway Inc.'s Warren Buffett during the financial crisis.