The Martinique Avenue home built in 1957 fills 9,300 square feet on one of the chic enclave's largest lots, My Florida Regional Multiple Listing Service data show.

Marked by its blue tile roof, the contemporary-styled home features four bedrooms, five bathrooms, a guest cottage, a large home theater and a full gym.

Sullivan bought the two-story home in 1994 for $1.2 million, property records show, and over the past five years added a new spa and dock.

Sullivan founded OSI Restaurant Partners, now called Bloomin' Brands, in the late 1980s, and the Tampa-based group now owns Outback, Carrabba's Italian Grill, Bonefish Grill, Fleming's Prime Steakhouse and Roy's.

Sullivan serves on Bloomin' Brands' board of directors and is a partner in MVP Holdings, a group of former Outback executives that opened fast-food chain PDQ and the Carmel Cafe & Wine Bar.

Realtor Toni Everett listed Sullivan's home in April. The buyer, who agents would not name, paid the $3.99 million listing price in cash.

"It's the most stunning, coolest house, I can't even tell you," selling agent Katherine Douville said. "Every room is just more opulent than the other. Who would ever even leave the house?"