MW The real estate of Open AI CEO Sam Altman: From a San Francisco 'lemon' to a Hawaii mansion

By Charlie Lankston

He also has a ranch in the Napa Valley.

Sam Altman's company OpenAI has made a groundbreaking $6.4 billion purchase, acquiring a fledgling devices company started by a former Apple $(AAPL)$ iPhone designer-a deal that was announced with much aplomb by the two tech founders.

In a statement shared on OpenAI's website, San Francisco-based Altman, 40, voiced his excitement over the acquisition of the startup, called io, while revealing that he had been "quietly collaborating" with the company's founder, Jony Ive, for two years.

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"The io team, focused on developing products that inspire, empower and enable, will now merge with OpenAI to work more intimately with the research, engineering and product teams in San Francisco," he wrote.

The all-stock deal is OpenAI's largest acquisition to date, according to the Wall Street Journal, and will see Altman working with Ive on a design for AI "companions," which he reportedly told his employees about one day before announcing the io acquisition.

Altman's purchase of the company comes just a few months after he made a rather hefty personal purchase in the form of three San Francisco homes, which he snapped up in January for $12.8 million each, according to property records.

The three dwellings are all located next to a historic six-bedroom, seven-bathroom Russian Hill mansion that he purchased for $27 million in 2020-before later becoming embroiled in a bitter and lengthy legal battle with its developer, Greg Malin, and his company, Troon Pacific, over claims that the home was "plagued by shoddy construction."

Altman, who filed the 2024 lawsuit via the LLC through which he purchased the 1907 home, claimed in legal documents seen by Realtor.com that Malin's company carried out "substandard work" on the home to save money during its multiyear renovation project.

"Owner ... alleges that developer skimped on competent or qualified construction managers, designers, and contractors for the development of the property," the filing states.

The suit adds that Altman had no "prior knowledge of the rancor, poor supervision, shoddy workmanship, corner-cutting, and financial embezzlement" he believes were involved in the project when he purchased the home.

Altman's LLC "entered into negotiations to purchase what it believed to be a beautiful, luxury home in San Francisco," it goes on. "When first put on the market, it was reported to be the most expensive home listing in San Francisco history, and it seemed obvious why."

The filing then calls attention to the home's most appealing amenities, including "stunning views," floor-to-ceiling glass doors that provide an indoor-outdoor setting, an elevator, a garden with 100-year-old olive trees, a historic cottage, and an infinity pool that overlooks downtown San Francisco.

However, Altman's lawyers claim that, after buying the home, which was described as a "lemon" in the filing, he discovered a wide range of "pervasive defects," including issues with drainage, plumbing, waterproofing, and sewer systems.

The lawsuit claims that repairs to the home would cost more than $4 million-and notes that the LLC connected to Altman was seeking unspecified damages from Malin and Troon Pacific, as well as interest and legal fees.

Altman's lawsuit is ongoing-however, it appears that he plans to hold on to the property and potentially expand it with the purchase of the three adjacent dwellings, which were all bought together for a total of $38.5 million, as first reported by The Real Deal.

The three homes are all registered to the same LLC, which is managed by Altman's cousin, Jennifer Serralta, who also oversees the LLCs connected to his other property purchases.

Much like the OpenAI CEO's original Russian Hill home, the properties were all built in the early 1900s and had previously been purchased together to form a large compound by their previous owners in 1994, records indicate.

The dwellings were the latest in a line of real estate acquisitions made by the tech mogul, who boasts an awe-inspiring collection of homes beyond his San Francisco holdings.

In November 2023, Business Insider reported that Altman had quietly snapped up an enormous estate in Hawaii in July 2021 for $43 million.

The 12-bedroom dwelling is located in Kailua-Kona on the Big Island and sits next to a reconstruction of the temple of King Kamehamela I, the first ruler of the Kingdom of Hawaii.

A Google $(GOOGL)$ Maps view of the oceanfront home reveals that it boasts a tennis court, swimming pool, and multiple guesthouses.

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Per Business Insider, Altman has a company registered to an adjacent address-the Sam Altman Qualified Opportunity Fund-and has previously shared an image of himself wakesurfing in Hawaii.

The home no doubt provides the OpenAI CEO with an idyllic beach escape, that is when it doesn't feel like spending time at his other vacation abode, a stunning ranch in Napa, Calif., where he and his husband, Oliver Mulherin, spend many of his weekends, according to the New York Times.

Altman invited a Times reporter, Cade Metz, to visit the home in 2023, with the resulting article noting that the 25-year-old home had been remodeled to "look both folksy and contemporary."

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The report noted that Altman, who is a vegetarian, and his then-partner were raising beef cattle on the land surrounding the home, which was tended to by farmhands, who also grew wine grapes on the property.

According to records, the ranch-which spans a staggering 950 acres-was purchased for $15.7 million in 2020, having initially been listed for $25.5 million.

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Property records show that the ranch, named Green Valley Ranch, was purchased through an LLC that Altman's cousin, Serralta, is also the manager of.

At the time of the sale, reports revealed that the ranch had previously been owned by a group of eight men, who had used the property "communally" for 42 years.

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One of those men, Hollywood lighting designer Bob Dickinson, told the CT Post that the buyer, who had "asked to remain nameless," had a "complete passion for the land."

"This little postage stamp of indigenous undisturbed California, it's hard to explain how marvelous it is to live where there are still river otters on your property and oaks that are centuries old," said Dickinson.

"He gets it. He's enthusiastic about it. He's not a group like we were, but he has a very close family and I think his motivation is to make it the same kind of community experience with his family and friends."

The original listing noted that the ranch was made up of nine parcels of land that were home to five "unique residences": the main ranch house, a terra guesthouse, a meadow house, a "Palladian-inspired lake house," and a "charming artist house."

This story originally ran on Realtor.com.

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May 27, 2025 05:02 ET (09:02 GMT)

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