With a market cap of $1 trillion, Walmart is the 10th most valuable public company in America, ranking behind the likes of Nvidia, Microsoft and Berkshire Hathaway. But it’s the only member of the four-comma-club that Forbes considers a family business, thanks to the 44% ownership stake retained by the descendants of Sam Walton, who have chaired the company since his death in 1992. The retail giant easily tops Forbes’ new list of America’s most valuable public family firms, worth nearly ten times as much as the next company.

The 25 publicly traded family businesses on Forbes’ latest ranking are behind the storage units where we keep our stuff (Public Storage), casinos where we gamble (Las Vegas Sands) and the stores where we buy our favorite sports equipment (Dick’s). They make some of the most popular brands of cars (Ford), cosmetics (Estee Lauder) and chicken (Tyson). And they hail from all across the nation, based in 15 states, from Nevada to Michigan to Maryland.

The most valuable public family business, after Walmart, is $97.1 billion (market cap) Comcast, which is run by chairman and CEO Brian Roberts, the son of founder Ralph Roberts (d. 2015), whose family still controls 33% of the company’s voting rights despite owning just 1% of the stock. The oldest of the top 25 is North Carolina-based First Citizens BancShares, which was founded in 1898 and taken over by long-time employee Robert Powell Holding, the grandfather of current chairman and CEO Frank Holding Jr., in 1935. One family, the Murdochs, actually has two companies that made the top 25: Fox and News Corp, which split in 2013.

Defining what counts as a family business can be tricky, so Forbes consulted with five experts in the field to come up with our methodology, which takes into account factors like family economic ownership (a minimum of 10% unless voting control is greater than 33%) and executive and board roles. We also published our first ever rankings of America’s Largest Family Businesses by revenue and America’s Top 25 Most Valuable Private Family Businesses this week. No companies run only by first generation founders were included on any of these lists.

Here are the top 25 most valuable public family businesses (market caps are as of May 1):

Market Cap: $1 trillion

Headquarters: Bentonville, AR

Sam Walton changed shopping forever when he opened the first Walmart store in Rogers, Arkansas, in 1962. In February, the 11,000-location leviathan became the first brick-and-mortar retailer to boast a $1 trillion market cap. Walton’s heirs still own 44% of the $713 billion (revenue) company. Son Rob Walton took over as chairman when his father died in 1992 and handed the reins to his son-in-law Greg Penner in 2015.

Market Cap: $97.1 billion

Headquarters: Philadelphia, PA

Ralph Roberts (d. 2015) bought a small subscriber TV system in Mississippi in 1963 and built it into a cable giant. Son Brian took over as chairman and CEO in the early 2000s and acquired AT&T Broadband, NBCUniversal and British broadcaster Sky. The Roberts family owns 1% of $124 billion (revenue) Comcast but has 33% voting power.

Market Cap: $96.1 billion

Headquarters: Nashville, TN

Doctor Thomas Frist Sr. (d. 1998) cofounded Hospital Corporation of America (now HCA Healthcare) with his son Thomas Jr. in 1968. The Nashville-based company now owns nearly 190 hospitals across the U.S. and United Kingdom. Thomas Jr., 87, and his family own 32% of $75.6 billion (revenue) HCA, and his sons Thomas Frist III and William Frist are directors.

4. Marriott International

Market Cap: $94 billion

Headquarters: Bethesda, MD

The hotel giant with 9,700 properties across 143 countries got its start in 1927,........

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