Every kid in Philadelphia grows up deeply invested in their local sports teams. The city is internationally renowned for its die-hard fans who ride for their teams like medieval knights carrying banners into battle.

Most people never come close to owning their local sports team. But 76ers part-owner and Philly native David Adelman, driven by a lost game of HORSE at age 11, a lifetime of Philly fandom and a career in property management and investing, asked one simple question: Why not?

Behind every great entrepreneur is a great mentor, and Adelman is no exception. He was introduced to the property management business at just 11 by his “uncle” Alan Horowitz, founder of Campus Apartments, now one of the largest providers of on- and off-campus housing in America, with some $2 billion of properties across 80 schools in 23 states.

“Alan wasn’t a sophisticated guy in a business sense,” Adelman recalls. “He didn’t go to college, but he was a genius with math” — something that eventually rubbed off on Adelamn. “He was just like a pal even though he was 30 years older,” Adelman recalls. “He taught me the value of loving what you do. Learning that early on was a gift for me.”

Along with founding campus apartments, Horowitz has another equally meaningful legacy in Philly. He’s known as the resident 76ers superfan, who can be found sitting courtside in his custom #76 SIXTH MAN jersey.

Adelman and Horowitz often played basketball together in Adelman’s youth, where the “sixth man” showed the 11-year-old Adelman that he could do more on the basketball court than just look cool.

“Alan was very competitive, and he loved to bet,” Adelman recalls with the smile of someone who’s told this story a million times. “One day, we were playing HORSE, and he asked me to place a bet.”

Most adults would let an 11-year-old child win. Not Uncle Alan. He took young David for everything he had, from his football to his baseball glove to his grandparents’ birthday money.

“It didn’t sink in until I woke up the next day and realized I couldn’t go play sports,” Adelman laughs.

Instead, he went down to Horowitz’s office to retrieve his things. Rather than leaving with his things, he found himself with a new job stacking lumber and sweeping sawdust in the warehouse to work off his debt. He ended up doing that every week for a month, until he finally earned back his belongings. That was enough to ignite a fire in young Adelman.

Becoming a man

Two years later, Adelman had his Bar Mitzvah — and walked away with about $2,000 in gift money.

“My parents wanted me to give it to my grandpa, who was a stockbroker,” Adelman says. “But I said no. I’m going to give it to Uncle Alan, and I’m gonna do what he does.”

So the 13-year-old hopped into Horowitz’s Corvette and cruised around Philly, touring the buildings his “uncle” owned.

“We get to one building, and it’s the biggest one he has,” Adelman remembers. “I told him, ‘Stop here.’ He was like, ‘What do you mean?’ I said, ‘I want to invest in this one.'”

There was no contract, no formal agreement, just a 13-year-old trusting his mentor with the first real money he’d ever had.

Horowitz didn’t let him down. He treated Adelman like a true partner, even giving him a small monthly dividend.

“I remember he’d be like, ‘You made $200 this year, that’s a 10% return on your investment,'” Adelman says.

As he grew older, Adelman started taking on more responsibility at Campus Apartments, flourishing under Horowitz’s guidance and becoming CEO at just 25. Not long after, he had the idea that would define his career.

“I realized all these students needed a place to live,” he explains. “We’re just renting out bedrooms. We’re not inventing anything new here. So why can’t we institutionalize it?”

Horowitz — older now, and already a local legend — wasn’t especially interested in scaling nationally. But he trusted his mentee’s instincts and let Adelman take the reins. In 2006, Campus Apartments raised $300 million in a private funding round, the largest in student housing at the time. From there, it was (mostly) smooth sailing.

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The next chapter

Adelman was eyeing the Sixers long before he had the money to make it happen. The idea first crossed his mind in 2012, when the team went up for sale, and he and his close friend Michael Rubin knew the owners.

“We had two problems,” Adelman snickers. “One, we were both building businesses and extremely busy. And two, we didn’t have the money.”

Rubin ultimately bought a minority stake when Josh Harris and David Blitzer acquired the team through Harris Blitzer Sports & Entertainment. Adelman stayed close from the outside, becoming a trusted ally of the organization and building relationships with both Blitzer and Harris, even doing some business together.

A few years later, as Rubin started moving deeper into sports betting, both he and Adelman could see the writing on the wall: Rubin would eventually have to step away from his role with the Sixers. And who better to take his place than your billionaire best friend — who happened to be mentored by the team’s most devoted fan?

“People always ask if it was a tough negotiation with Michael,” Adelman says. “It wasn’t even a three-minute conversation.”

Today, after Harris and Blitzer (HBSE), Adelman is the third-largest shareholder of the 76ers — and the hometown face of the franchise.

HBSE owns more than the Sixers; it’s one of the largest sports ownership groups in the country, with controlling stakes in the New Jersey Devils and Washington Commanders, plus a piece of Formula 1.

“We’re all active in different ways,” Adelman says of the partners. His lane is real estate, which puts him front and center on one of the group’s biggest undertakings: a new $1.3 billion arena.

“I always ask, ‘Why can’t Philadelphia have nice things?'” he jokes. “Well, I’m going to build the best arena — the best live entertainment venue — in the world, right here in Philadelphia.”

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The arena is slated to open by 2030 and will also welcome the city’s new WNBA franchise, which will play its inaugural season there.

“What do you think the overlap is between Valkyries and Warriors season-ticket holders?” Adelman asks. “It’s 4%.”

For a sharp businessman — and a girl dad who coaches his daughter’s basketball team — bringing a women’s franchise to a city that rallies around its sports teams feels like a natural win-win.

In addition to his role as CEO of Campus Apartments, Adelman is also the founder of Darko Capital, a family office involved in everything from alcohol to advanced manufacturing. He likens investing to being the general manager of a sports team, where the job is to “draft” the best businesses and support them without being overbearing.

“You have to learn when you’re an investor and when you’re active in the business,” he explains.

Ultimately, no matter how significant an impact Adelman makes as an owner of his hometown team, he recognizes that the Sixers are bigger than any one person. “

Josh, David, and I — we’re all fans,” he says. “We don’t view this team as ours. The team belongs to the city. We’re just the current stewards.”