The duo, ranked sixth on Forbes’ 2025 Malaysia 50 Richest list with $5.2 billion in net worth, are the sons of the late Malaysian tycoon Lee Shin Cheng, who made his fortune with palm oil giant IOI Corporation and developer IOI Properties. The two businesses are commonly referred to together as the IOI Group.

The late Lee’s journey to riches is a quintessential example of rising from humble beginnings. Raised on a rubber plantation in Jeram, Kuala Selangor, where his father ran a Chinese food business, Lee dropped out of school at age 11 to sell ice cream by bicycle to help support his family and only resumed his education four years later.

He later worked at another rubber plantation, where he rose through the ranks to become an estate manager by 30. In 1975, he started a property firm that would later become IOI Properties. Seven years on, he acquired Industrial Oxygen Incorporated, which would be renamed IOI Corporation in 1995, and ventured into the palm oil business, according to The Business Times.

By the time he passed away in 2019, Lee had transformed IOI Corporation into a global palm oil player with operations across eight countries and IOI Properties into one of the biggest property developers in Malaysia, with a strong presence in Singapore and China. He had consistently ranked among Malaysia’s richest since 2007.

Today, IOI Corporation has a market cap of RM22.52 billion (US$5.3 billion) while IOI Properties is valued at RM10.57 billion, according to their website.

Billionaire brothers take up the mantle

After their father’s death, Yeow Chor and Yeow Seng inherited stakes in IOI Group, becoming billionaires and taking on leadership roles at the conglomerate.

Yeow Chor, 58, has been steering the palm oil division as group managing director and CEO of IOI Corporation.

Meanwhile, Yeow Seng, 46, leads the real estate arm as group CEO of IOI Properties. The London-trained lawyer is married to Yeo Bee Yin, Malaysia’s former environment minister.

The division of responsibilities between the brothers was by design. In a 2024 phone interview with ForbesYeow Chor explained, “Our father was deeply passionate about both ventures,” and believed each son should have space to chart his own path.

He recalled that their father emphasized being “very hands-on” in business—an approach the brothers continue to embrace as they often visit the group’s plantations and construction sites.

“Our vision is we want to be a leading player in both palm oil and property,” Yeow Chor said. “There’s room to grow in both.”

Although the family’s wealth still largely stems from palm oil, its property arm has become an increasingly important pillar, offering stability against the fluctuations of the commodities market.

IOI Properties has steadily expanded its footprint in Singapore. Its residential portfolio in the city-state includes high-end developments such as Seascape and Cape Royale in Sentosa Cove, built in collaboration with real estate firm Ho Bee Land, as well as The Trilinq in Clementi and Cityscape@Farrer Park.

It also developed other projects such as the IOI Central Boulevard Towers in the Marina Bay area and is planning a major addition nearby: W Singapore – Marina View, a 350-room hotel set to open in late 2028.

It co-developed the South Beach mixed-use complex with billionaire Kwek Leng Beng’s CDL after they became joint venture partners in 2011.

On Wednesday, CDL said it would sell its 50.1% stake in the project, valued at about S$2.75 billion (US$2.1 billion), to the Malaysian developer, giving it full ownership. Yeow Seng called the purchase “a significant strategic expansion” in a key regional market.

Previn Singhe, CEO of property consultancy Zerin Properties, called the deal well-calibrated as it allows CDL to unlock capital for reinvestment and gives IOIProp full ownership of a prized asset.

“It is a win-win, and a great example of a mature, cross-border transaction between two seasoned developers,” he told The Star.