Mark Zuckerberg responded to the underground facilities at his Kauai estate on Bloomberg's "The Circuit," stating that it is merely a small shelter, like a basement, and denied that the entire ranch is a doomsday bunker. He added that it serves as a hurricane refuge space outside the main house, office, and storage, believing that the scale has been exaggerated by outsiders.

Public planning documents do not align with his statements. Wired reported in December 2023 that Koʻolau Ranch spans approximately 1,400 acres, with two main houses connected by tunnels, featuring over 5,000 square feet of underground shelter, including living areas, a machine room, and an escape ladder, with doors made of metal filled with concrete. Hawaii News Now and subsequent reports noted the underground storm shelter is nearly 4,500 square feet. The median size of new single-family homes in the U.S. Census Bureau's second quarter of 2024 is 2,161 square feet, making this basement larger than most users' entire homes.

The land has been purchased in batches since August 2014. Forbes and local reports state that he paid over $100 million for about 700 acres on Kauai's North Shore. Wired estimates the land acquisition at about $170 million, with main construction permits around $100 million, totaling over $270 million, which they claim is likely still an underestimate. The plans also include self-sufficient energy and food, a 55-foot diameter water tank, over 12 buildings, at least 30 bedrooms and 30 bathrooms, and 11 treehouses. Spokesperson Brandi Hoffine Barr declined to comment on the scale and bunker attributes. Contractors signed strict confidentiality agreements, and a former contractor described the place as resembling a fight club, unable to discuss it.

On December 30, 2016, his company filed a quiet title and partition lawsuit in Hawaii state circuit court against small parcels of land traditionally allocated to descendants of native Hawaiians, which are surrounded by his property. There are over 300 defendants in the case, including deceased individuals; one parcel of about 2 acres dates back to land purchased by Manuel Rapozo in 1894, valued at approximately $1.1 million by local newspapers. After backlash, he and Priscilla Chan wrote to a local newspaper expressing regret for not taking the time to understand the quiet title process, now realizing it was a mistake, and withdrew the lawsuit. Construction has not stopped.

The ranch is currently marketed for cattle raising and beef production. Wired reported that he has held two corporate events at the estate, larger than a private vacation home. An English report in October 2026 estimated his net worth at about $258 billion. He referred to the basement as a basement, while the planned area is still about twice that of an average new home.

This is a case of private capital acquiring space, not a corporate merger. The seller is the coastal and ranch land that can be transferred, while the buyer is responsible for self-sufficient water, food, and underground exits; caught in between are families that can only claim rights based on traditional shares. The withdrawal of the lawsuit blocked forced sales but did not stop subsequent land grabbing. Beneficiaries are the completed gated community and the construction chain that signed confidentiality agreements, while descendants named in the lawsuit are under pressure, surrounded by large landowners.

Source: Public Information