“If we always focus on our customers, the business will grow and we will continue to be a strong and healthy company, which allows us to invest in our employees and customers and support charitable organizations in our communities,” Fidelity spokesman Vincent Loporchio said in an emailed statement. He declined to comment on the family’s net worth.

Diversification has always been a part of Fidelity’s DNA. That’s evident in how Abby has reoriented the firm in the ever-shifting whims of finance and how the Johnsons invested their personal wealth.

Most of the world’s richest clans owe their fortunes to well-stewarded companies. As they grow and throw off cash, the families usually invest the proceeds with diversification in mind, hedging against downturns in specific industries and buying easy-to-sell assets when heirs need money for a villa or to start new ventures. For a family business that makes luxury handbags, diversification might mean an index fund.

So what does it mean for a family that actually makes index funds?

A lot of hard assets, for starters: tangible investments like real estate and Texas shale. But it also means high-growth tech and pharmaceutical startups. Unlike many families that separate personal investments from the operating business, the Johnsons’ interests are intertwined with FMR LLC, the parent of Fidelity Investments, of which they own 49%. FMR employees hold the rest.

Gummy Pants
The hodgepodge nature of FMR reflects both Ned III’s entrepreneurial leanings and the advantages of running a closely held company. With no broad base of anonymous shareholders to answer to and no stock price to worry about, the Johnsons have been able to use the entity to invest in areas unrelated to asset management.

About three decades ago, Ned III set up Fidelity Capital, a division that resembled a venture capital firm, investing in assets well outside its core focus, like real estate, catering and staffing. Later — legend has it — he got gum on his pants in a taxi, so he started his own fleet in the 1980s and built it into one of the country’s largest chauffeured car services before selling it in 2013.

In the 1990s, Fidelity Capital founded City of London Telecommunications, an early competitor to former state monopoly British Telecom. The Johnsons along with other FMR shareholders and Fidelity’s sister company, Fidelity International, which in turn is about 40% owned by the family, still control the $4.5 billion company, now known as Colt Group.

Seaport Place
To see the quiet influence of the Johnson empire, look no further than the Boston seaport. Twenty-five years ago, it was a barren fishing pier bounded by crumbling parking lots. Today it’s chockablock with gleaming office towers and waterfront cafes.

On a recent sweltering afternoon, a smattering of tourists and locals lounged on strips of grass that fringe the office buildings, now mostly empty. The sleepy vibe contrasts with pre-Covid times, when thousands of workers flooded the neighborhood daily.

Seaport Place, a linchpin of the area’s overhaul, was the work of the Johnsons. Pembroke Real Estate, a property company run by Abby’s younger brother, Edward C. Johnson IV, manages 2.2 million square feet of office, retail and hotel space on the northern edge of once-gritty South Boston. Pembroke oversees commercial properties owned by FMR and Fidelity International, according to its website.