Andy Beal Photography / Flickr
His enormous purchase includes pretty much everything on the island - small businesses like local restaurants, shops, and galleries, and large businesses like the two Four Seasons hotels on the island.
He owns two golf courses, the community swimming pool, the water company, and a cemetery. He also owns nearly a third of all of the island's housing.
One thing he also now unexpectedly owns: about 400 feral cats.
Buzzfeed recently published an in-depth look at these cats, residents of the Lanai Animal Rescue Center, a sanctuary and popular tourist destination on the west side of the island.
"They're the island's cats," founder Kathy Carroll said to Buzzfeed.
Many of the cats were rescued from the dump and other sites near the Four Seasons. About 30 cats have been adopted from the shelter since last summer.
Buzzfeed notes that Ellison has not yet visited the cat shelter, though his love for cats is well known.
According to an anecdote in his 1997 biography, "The Difference Between God and Larry Ellison (God Doesn't Think He's Larry Ellison)," Ellison's cat Clio died while he was away on a business trip. Ellison apparently insisted on having the cat buried under her favorite tree.
rickh710/Flickr
A view of a beach on Lanai.
Ellison's plans for Lanai are still rather mysterious, and the transition of ownership to the Oracle billionaire has been controversial among residents. In an attempt to woo locals, Pulama Lanai, Ellison's development company, has completed updates to Lanai City's swimming pool and movie theater.
Ellison has previously said he wants to transform the island into a "laboratory for sustainability," complete with a solar power system, electric car infrastructure, and a seawater irrigation system for organic farms, according to Honolulu Magazine.