Updated

Bill Gates is the richest person in the world — but one retired New York hedge-fund mogul thought the software pioneer’s Giving Pledge was “practically worthless.”

Robert W. Wilson, a well-known philanthropist who had given away $600 million of his fortune as of 2013, abruptly turned aside Gate’s 2010 request that he sign the Giving Pledge.

The pledge pushes billionaires to give away a bulk of their fortune while they are alive, or in their will.

Wilson found especially problematic the pledge’s loophole that allowed signers to gift their wealth to a family-controlled foundation.

“And these foundations become, more often than not, bureaucracy-ridden sluggards,” Wilson wrote to Gates in a June 2010 e-mail, a copy of which was obtained by the website BuzzFeed.

“I’m going to stay far away from your effort,” Wilson told Gates in the same e-mail.

Last week, Wilson, 86, took his own life by throwing himself from his luxury Upper West Side high-rise, just a few months after suffering a debilitating stroke.

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