Yes, the Biltmore Estate in Asheville, North Carolina, remains privately owned and operated by the descendants of George Washington Vanderbilt II. Unlike many Gilded Age mansions that were turned over to the government or non-profits, Biltmore is still a family business managed by The Biltmore Company. Currently, the estate is overseen by the Cecil family, who are direct descendants (George Vanderbilt's grandson, William A.V. Cecil, was instrumental in turning the estate into a profitable tourist destination). The company operates the 175,000-square-foot house, the massive gardens designed by Frederick Law Olmsted, a luxury hotel, and a successful winery. While they sold off much of the original 125,000 acres to the federal government to create the Pisgah National Forest, the family still retains approximately 8,000 acres, ensuring that the "largest privately owned home in the United States" stays within the Vanderbilt lineage for future generations.
Yes, the Biltmore Estate is still owned by the Vanderbilt family, though it is managed by their descendants rather than being under direct family control as it once was.
So, while the Vanderbilts don’t “own” it in the traditional sense of personal residence, they still control it through a corporate structure.