Here is a quiz almost everyone fails. Name the largest private company in the United States. Not Apple or Walmart, those are public. The answer is a firm most people have never knowingly bought anything from, though it...
Here is a quiz almost everyone fails. Name the largest private company in the United States. Not Apple or Walmart, those are public. The answer is a firm most people have never knowingly bought anything from, though it touches a large share of what they eat: Cargill, of Minnetonka, Minnesota, with $154 billion in revenue in fiscal 2025, $160 billion the year before, and a record $177 billion the year before that (Star Tribune; Star Tribune).
Cargill has been in business for 160 years. It has never gone public. Roughly 100 descendants of two intertwined families, the Cargills and the MacMillans, together own an estimated 88 percent of it, and Forbes has counted 21 billionaires among them, more than any other family in America (Forbes; Cargill family, Wikipedia).
No single decision produced this. What produced it was a small set of conventions, applied for a century and a half, about how much money the family takes out, how the family gets cash without selling the company, and who is allowed to run the thing. Every one of those conventions scales down to a family with one shop, one farm, or one rental house.
William Wallace Cargill was twenty years old when the American Civil War ended. That year, 1865, he bought a grain storage business in Conover, Iowa, a village at the end of a railroad line, and began buying, storing, and moving farmers' grain (Cargill family, Wikipedia; Cargill, Wikipedia). It was the least romantic business imaginable: warehouses, freight rates, moisture content. W.W. ran it for almost 40 years as it spread along the new railroads of the upper Midwest (Cargill family, Wikipedia).
The second name on the door arrived by marriage. John H. MacMillan Sr. married W.W. Cargill's daughter Edna, and after W.W. died in 1909 it was MacMillan who steered the indebted firm through the crisis that followed the founder's death and set the pattern of disciplined, unglamorous management the company still cultivates (Cargill family, Wikipedia; Creaghan McConnell Gould). From then on the enterprise belonged to two families braided into one shareholder group, which is why the clan is known today as the Cargill-MacMillan family.
For the next century the company did what grain merchants do, at ever larger scale: trading, shipping, processing, meat, starches, sweeteners, salt, animal feed, and financial risk management, across dozens of countries. Family members ran it for generations. The last of them in the chief executive's chair was Whitney MacMillan, who led the company from 1976 to 1995; since his retirement, every CEO has been a professional from outside the family (Cargill family, Wikipedia). The family kept the ownership. It gave up the steering wheel. Hold that thought, because it is one of the three load-bearing mechanics.
The heart of the Cargill system is an arithmetic convention that sounds almost too simple to matter. The family takes out little and leaves in much. By long-standing practice, dividends to the family run around 20 percent of annual earnings, with the other roughly 80 percent retained and reinvested in the company, year after year, decade after decade (Creaghan McConnell Gould; Grokipedia, Cargill family). For comparison, payout ratios at large public companies often reach 50 percent (Creaghan McConnell Gould).
Run the logic forward. A company that reinvests four-fifths of what it earns compounds; a family that consumes four-fifths of what its company earns liquidates in slow motion. Multiply that difference by 160 years and you get the gap between Cargill and the thousands of once-thriving family firms that no longer exist. The individual Cargill-MacMillan heirs are not modestly wealthy, 21 of them are billionaires, but their wealth sits inside the machine, not in extracted piles beside it (Forbes).
Notice what makes the rule work: it is a convention, not an annual argument. Nobody renegotiates the split each year based on who needs a new house. The number is settled, so the family's expectations are settled, so the company can plan on keeping its earnings. The discipline is not in any single year's restraint. It is in removing the question from the table.
Around the fourth and fifth generations, every wealthy family meets the same visitor: the heir who wants out. By the early 1990s Cargill had roughly 90 family shareholders, some of them far from the business, and pressure built from members who wanted to convert paper wealth into spendable money. On more than one occasion parts of the family pushed for the obvious exit, taking the company public so they could cash in (Creaghan McConnell Gould; MatrixBCG).
An IPO would have solved the liquidity problem by creating a permanent new one: outside shareholders, quarterly earnings theater, and the slow-motion loss of control that has dissolved family firms from Guinness onward. Cargill chose a different instrument. In 1992 the company created an Employee Stock Ownership Plan and executed a buyback in which family shareholders sold about 17 percent of their stock for roughly $700 million, with the shares going to employees rather than to the public market (Grokipedia, Cargill family; Creaghan McConnell Gould).
Look at what that structure did. The impatient got real money. The patient kept a private company. The buyers were insiders whose interests ran with the firm. And the family's collective ownership stayed large enough, the estimated 88 percent of today, that control was never in question (Forbes). The pressure was real, and instead of denying it, the family built a valve.
They did it again, at larger scale, in 2011. Margaret Cargill, a granddaughter of the founder, died in 2006 and left her stake, about 17 percent of the company, to her charitable organizations, which needed to turn shares into grant-making money. Rather than go public to create that liquidity, Cargill split off its 64 percent stake in the fertilizer company Mosaic, 286 million shares valued at $24.3 billion overall, and exchanged Mosaic stock for the Cargill shares held by the estate, with the Margaret A. Cargill philanthropies receiving Mosaic shares valued around $7.4 billion (Twin Cities Business; Mosaic press release; Loeb & Loeb). A multibillion-dollar exit was engineered for one shareholder, and the company remained private. That is what mature liquidity planning looks like: the family sells assets, never the citadel.
Three conventions carry this whole story, and none of them requires a grain empire.
One: fix the retention rule in writing. Decide what percentage of your family enterprise's profit, your shop, your rentals, your farm, is available for consumption, and what percentage is locked for reinvestment. Cargill's split is roughly 20 to the family and 80 to the machine. Choose your own numbers, but choose them once, write them into the family agreement, and stop relitigating them every season. The rule will feel restrictive in good years. That is exactly when it is doing its work.
Two: build liquidity valves before someone needs one. The heir who wants out is not a traitor; he is a certainty. Plan for him now. The Cargill toolkit translates directly: an internal buyback fund the business feeds annually so it can purchase shares from members who want to exit at a pre-agreed valuation formula; permission to sell a side asset, the Mosaic move, rather than the core; and a written rule that shares are offered inside the family or to the business before anyone outside sees them. A family with valves loses members occasionally. A family without valves loses the company all at once.
Three: separate owning from running. Since 1995 no family member has been Cargill's CEO, and the company has thrived under professionals while the family governs as owners (Cargill family, Wikipedia). The family-scale version: the business should be run by the most competent available person, and if that is not your child, your child's job is to be a skilled owner instead, reading accounts, setting standards, hiring and firing managers. Teach heirs that ownership is a profession in itself. The families that insist every generation must produce a manager eventually get a bad one, and one bad manager can spend a century of retained earnings.
W.W. Cargill bought one grain warehouse in 1865. Six generations later, about 100 of his and John MacMillan's descendants own 88 percent of America's largest private company, because the family adopted a few dull conventions and never broke them: take a little, retain a lot, build exits for the restless, and let professionals run what the family owns.
Here is the decision in front of you. Will you write your family's retention rule this month, one sentence stating what share of profit gets consumed and what share stays in, and a second sentence describing how a family member can ever cash out without forcing a sale of the whole? If those two sentences do not exist, your family currently has the default plan, which is this: everything gets decided in the worst possible year, by the angriest people in the room, under the most pressure. Cargill retired that plan 160 years ago. Yours is still running.