The Bloomberg Bunch
The Bloomberg Bunch
Proto-billionaires in 1982: from left, Michael Bloomberg, Charles Zegar, Tom Secunda, and Duncan MacMillan

In 1982 these four men, founders of a new company called Innovative Market Systems, were featured in a New York Times article about startups. Could any of the four have imagined that their venture, soon to be renamed Bloomberg LP , would in less than 30 years turn them into billionaires? And beyond that, make each a signer of the Giving Pledge?

Well, no, of course -- even though Michael Bloomberg, who's the curly-head at far left, never lacked for confidence that he could do almost anything.

Mike Bloomberg's fame as predominant owner of that company, three-time mayor of New York City, and expansive philanthropist will guarantee him, as he once predicted, "a long obituary." The nonfame of the other three men--all minority owners of Bloomberg LP --is one of the remarkable elements of the Giving Pledge list.

Next to Bloomberg in the photo at left is Charles "Chuck" Zegar, now 63, who was the technical genius--the rocket scientist--among the founders. No longer at Bloomberg LP , he has made a career out of not getting photographed. So the headshot of him on the first page of this story is lifted from the photo here.

Third and fourth in the picture are Tom Secunda and Duncan MacMillan, both still Bloombergers. Secunda, 57, a mathematician who also brought bond-trading expertise to the company, is today its product guru and culture-keeper. MacMillan, 73, focused on operations and product development in the startup and says his current job is "product support."

Mike Bloomberg, 69, signed onto the Giving Pledge in the first wave last summer and has enthusiastically backed the idea. The first exposure of the other three men to the drive occurred when they and their wives were later invited to a dinner of prospects held by Bloomberg at his foundation headquarters. We might guess that the Mayor regarded this as an invitation not to be refused. Soon after, all three prospects made the pledge, each co-signing with his wife--namely Merryl Snow Zegar, Cindy Secunda, and Nancy MacMillan.

The Bloombergers among the Giving Pledge signers now have a certain distinction. Facebook produced two billionaires on the list, Zuckerberg and Moskovitz, and Microsoft can claim three, Bill and Melinda Gates and Paul Allen. But only Bloomberg LP has put four of its tribe on the list.

Last updated June 20 2011: 4:17 PM ET