A Northwestern University economics graduate, he has transformed online pornography from a business based largely on ad-supported X-rated videos into a social-media service offering the alluring—and lucrative—illusion of companionship. OnlyFans now boasts more than 300 million users, many of whom pay fees for subscriptions to a creator’s page, pay-per-view videos and personalized interactions. 

Its creators include sex workers but also moonlighting amateurs, pop stars and other saucy celebrities who often offer explicit content for their paying subscribers. 

“OnlyFans completely changed the industry because it opened it up to the average person to be able to be a performer,” said Alana Evans, who has been in the adult-entertainment industry since 1998 and heads the Adult Performance Artists Guild union. 

Yet despite being a global king of porn, it would be an understatement to say Radvinsky keeps a low profile. The 43-year-old has mastered the art of staying unseen.

He doesn’t give interviews and stays away from industry events. A single photo of him smiling with his arms crossed has circulated on the internet for years. People who have worked with Radvinsky say they are bound by nondisclosure agreements.

Through an OnlyFans spokeswoman, Radvinsky declined to comment for this article.

But Radvinsky, who was raised outside of Chicago and now lives in Florida, is making a bid to climb the ranks of the world’s richest people. Radvinsky’s parent company, which owns OnlyFans, has sounded out banks and potential buyers, asking for as much as $8 billion, people familiar with the talks said.

Radvinsky’s fortune, including the value of OnlyFans, is already estimated by Forbes to be nearly $4 billion. British corporate records show that OnlyFans is hugely profitable—Radvinsky is its sole owner and collected nearly $1.3 billion in dividends in the five years ended in March 2024.

A multibillion-dollar exit would possibly allow Radvinsky and his wife, Katie Chudnovsky, to plow more money into philanthropy. He says on his personal website that he hopes to someday sign the Giving Pledge, which would be a public commitment to donating most of his wealth to charity. In a rare public appearance, Radvinsky attended a 2024 gala for a gastrointestinal research foundation on whose board his wife has served for over a decade.

At the gala, Chudnovsky, who now chairs the foundation, spoke about a $23 million grant program for cancer research that she and her husband had helped support.

“Because of the scientists behind the research we are funding, one miracle followed another. The advances will forever change the face of cancer treatment. And Leo’s here tonight proving that science and miracles go hand in hand,” she said.

The foundation’s YouTube account removed its video of that gala shortly after The Wall Street Journal mentioned it to OnlyFans. 

The site’s London-based parent company, Fenix International, was in talks earlier this year over a potential acquisition by a group led by Forest Road, a Los Angeles-based investment bank and advisory firm, according to people familiar with the talks.

It is now unclear if those talks are ongoing. Radvinsky and his team are moving forward with talks with another potential buyer described as their preferred option, one person said. 

Even an $8 billion price would be a considerable discount to what other fast-growing tech companies would fetch that are even close to as profitable as OnlyFans.

All of which raises the obvious due-diligence question for any transaction of this size: Who is the emperor behind the empire?

Born in the Soviet Union, Radvinsky moved to the Chicago area when he was a child. He spent at least part of his youth not far from Chudnovsky, another childhood Jewish émigré from the Soviet Union, who was just a couple of years behind him at Northwestern.

Radvinsky saw business opportunities in the salacious side of the internet while he was still a student at Glenbrook South High School in the suburb of Glenview.

High-school classmates say Radvinsky, who played competitive chess when he was as young as 10, was a smart, sometimes abrasive teen who liked to wear a leather jacket in defiance of the Abercrombie & Fitch-inspired prep styles of the time. At school, Radvinsky’s online business was a poorly kept secret.

That business was called Cybertania—its incorporation papers were signed by Radvinsky’s mother in 1999 when he was still a teenager. One of its first gambits was operating websites such as Ultimate Passwords, which he registered in 2000, that claimed to offer hacked passwords to porn sites.

Some of the hundreds of pornographic website names he owned, according to internet records, included names of celebrities and actresses popular at the time like Paris Hilton, Tara Reid, Britney Spears, Jessica Simpson, Shannon Elizabeth and Ben Affleck. Many of the sites promised links to various X-rated videos. 

Radvinsky’s business continued to grow and he started other corporations, including a website called MyFreeCams in 2004. It was the early days of what became known as “camming,” in which models blend casual chats with sexually explicit live content that their users pay for online.

Radvinsky and Chudnovsky married in 2008, under a crystal chuppah at a glitzy Chicago-area banquet hall, according to a wedding announcement in the Chicago Tribune. Chudnovsky, a lawyer who had her own practice, has in recent years described herself in charity bios as the general counsel of an “international privately held technology firm.” 

Chudnovsky said in a 2021 interview with an online women’s magazine that she is a mother of four children.

In 2018, Radvinsky was among the potential bidders for the once-iconic porn brand Penthouse in bankruptcy court, alongside PornHub’s parent company and Larry Flynt’s Hustler empire, according to court filings. 

Radvinsky didn’t win that auction, but soon afterward he made what would turn into a far more lucrative investment: He bought 100% of OnlyFans for an undisclosed amount.

At the time, it was a British company similar to MyFreeCams that sold users, dubbed Fans, subscriptions to a creator’s page of videos and photos. Tim Stokely, the site’s founder, later told the Financial Times that Radvinsky had emailed him strategic ideas and he had been impressed.  

Stokely declined to comment on OnlyFans or Radvinsky. He stepped down as chief executive in late 2021.

When Radvinsky bought the company, its U.K. corporate entity didn’t report revenue because it fell under what the U.K. calls the small-companies regime. By the next year, gross payments from users rocketed more than fourfold to about $308 million.

Under Radvinsky’s ownership, OnlyFans harnessed the power of other social-media platforms to boost sign-ups. Users discover their favorite purveyors of sexy memes on sites like Instagram and TikTok and then find their OnlyFans pages, which offer uncensored content for a price. 

The revenue model is simple: Subscribers’ payments are split so 80% goes to creators and 20% goes to OnlyFans. 

“He’s obviously coming in with a very clear strategic vision for how the flows of commerce work around these sites,” said Maggie MacDonald, who studies pornography platforms as a doctoral candidate at the University of Toronto and serves on an advisory board of Ethical Capital Partners, owner of the website PornHub. MacDonald called the OnlyFans model brilliant because the creators are motivated to market themselves. “He’s outsourced all of the labor of marketing to the ground floor.” 

Things really took off in 2020 as pandemic shutdowns left people looking for ways to make income and feel less lonely. The service added nearly 300,000 new users every day in 2021, according to British corporate filings. 

Around that time, Radvinsky and Chudnovsky moved to Florida. Their home, property records show, was a 10,000-square-foot mansion previously owned by tennis star Chris Evert. By 2023, Radvinsky had started living in a palatial South Florida duplex. That apartment, with soaring windows and ocean views, was purchased for more than $20 million.

Keily Blair, a former privacy lawyer, has been OnlyFans CEO for two years. At conferences and in interviews, she often plays down the idea that OnlyFans is pornography-centric and talks up its other offerings. The company has developed safe-for-work content on a TV streaming platform and done deals to bring on top athletes as creators. 

Blair told the Journal last year that the company doesn’t track how many of its creators offer adult content.

“We are a space for grown-ups to have grown-up content experiences. Sometimes that will include adult content, but often it can include sport, comedy, mixed martial arts,” she said. 

Write to Sam Schechner at Sam.Schechner@wsj.com and Katherine Sayre at katherine.sayre@wsj.com