Newsweek called him "Facebook's Russian Sugar Daddy" after his company, DST, engineered at least a half-billion-dollar stake. Forbes put the numbers even higher this month - an $800 million investment now worth as much as $7 billion.
Like Pincus, Milner is personally worth $1 billion, tying them with Eagles owner Jeffrey Lurie and about 70 others around the globe, Forbes estimated.
Tens of millions of people play such Zynga games as FarmVille, Mafia Wars, CityVille and Cafe World, which have been wildly popular on Facebook.
After naming the start-up after his bulldog, Chicago-born Pincus, 45, began raking in the chips with Texas Hold'Em Poker. Basically, the games are free but forking over real cash lets players advance more quickly - rising in the Mafia ranks, for example - or buy swankier stuff, like pink tractors.
That was a half-billion-dollar revenue stream last year, according to industry estimates.For virtual poker chips, pink tractors and their ilk.
Major credit cards accepted.
Offices have sprung up from Maryland to India and China, and rumors are that the company could go public this year, which would really put the zing - and ka-ching - in Zynga.
Skeptics doubt how long players will stay faithful, but Zynga keeps introducing new games - FishVille or FrontierVille, anyone? - and has been adding games for smartphones and iPads.
Another rumor: Zynga's working on its own game-playing site.
Even Jeffrey Katzenberg, the CEO of DreamWorks Animation, was envious, declaring last year that if he began a new career, "I said I would like to be Mark Pincus. . . . He has nailed the next killer app."
Pincus called Milner "a trusted adviser," who visited monthly "to give input, but it's a soft touch," according to Businessweek last year.
Milner's DST is also a major Internet force in Russia, raising $900 million in November by selling shares of Mail.ru, a Web mail service, on the London Stock Exchange.
Milner also invested $135 million in Groupon, the online discount dealmaker.
About two dozen people whom Forbes has listed as billionaires studied at the University of Pennsylvania, most of them at the Wharton School of Business - even if you don't count Wharton dropout Warren Buffett.
Worth an estimated $50 billion, he's the third richest man in the world, behind Microsoft founder Bill Gates ($56B) and Mexican telecom king Carlos Slim Helu ($74B).
Wharton's most famous grad might be presidential apprentice Donald Trump ($2.7 billion), who got his bachelor's there. Others with an undergrad degree include hedge fund founders Steven Cohen ($8B) and Daniel Och ($3.3B), supermarket chain heir Charles Butt ($5.3B), and Leonard Lauder ($6B) and Ron Lauder ($3.1B), sons of cosmetics queen Estee Lauder.
Among those with Wharton MBAs are leveraged-buyout tycoon Ronald Perelman ($12B); India's Anil Ambani ($8.8B); trucking prince Donald Schneider ($2.5B); junk-bond wizard Michael Milken ($2.1B); and Mortimer Zuckerman ($2.1B), best known as owner of the New York Daily News and U.S. News & World Report.
Another Wharton dropout is investor Nelson Peltz ($1B), who bought Snapple in 1997 for $300 million then sold it three years later for $1.5 billion, according to Forbes.
Among Penn alums who weren't at Wharton are casino developer Steve Wynn ($2.3 billion) and physician Phillip Frost ($2.3B), who made his mark in pharmaceuticals.
Also on the list were a handful of billionaires listed as residing in the Philadelphia area (but didn't go to Penn): West Chester's Hansjorg Wyss ($6.4B), who ran medical device maker Synthes for three decades; Coatesville's Campbell Soup heiress, Mary Alice Dorrance Malone ($2.3B); Bryn Mawr's microchip maven James Kim ($1.4B); Urban Outfitters founder Richard Hayne ($1.4B); and Eagles owner Jeffrey Lurie ($1B).
Falling off the list this year was philanthropist Dorrance "Dodo" Hamilton, another Campbell Soup heiress, of Wayne.
Contact staff writer Peter Mucha at 215-854-4342 or firstname.lastname@example.org.