Tom Guinney, one of the three co-founders of Utah’s Market Street Grill and Oyster Bar restaurants — and the man responsible for its signature clam chowder — died last week of natural causes.

He was 71.

Before his death, Guinney had sold all of the restaurants’ assets to an experienced — but unnamed —local restaurateur, spokesman John Becker told The Salt Lake Tribune. “Tom’s hope was that the Market Street Grill and Oyster Bar restaurants would continue to serve the finest, freshest seafood for many years to come."

The name of the buyer and the terms of the sale are confidential, Becker said, but "we anticipate it will be business as usual” for patrons and employees, who were informed of the sale shortly after Guinney’s passing.

Guinney’s death marks the end of an era for Salt Lake City’s dining scene. Nearly four decades ago, Guinney — along with business partners Tom Sieg and John Williams — opened the first Market Street Grill and Oyster Bar in downtown.

Sieg and Williams had opened the New Yorker in 1978 and brought Guinney, a California native with experience running a series of seafood restaurants, into the fold in 1980. Eventually, the three formed Gastronomy Inc., opening Market Street Broiler near the University of Utah — which they sold in 2014 — as well as Market Street Grill and Oyster Bars at the Salt Lake City International Airport and in Cottonwood Heights and South Jordan.

Sieg died in 2008 and Williams, who retired more than six years ago, was killed in a house fire in 2016 — the blaze set by his estranged husband — Craig Crawford.

Last October, Guinney, shocked the Utah dining community when he abruptly closed the New Yorker. The Williams estate owns the space; future plans are unclear.

Guinney had been the sole proprietor of the Market Street restaurant until Friday, when he died at the home of his daughter, Alexandra Bird, in Oregon City, Ore. A visitation will be held Monday at 6 p.m. at Neil O’Donnell and Sons Mortuary, 372 E. 100 South. A funeral Mass will be Tuesday at noon at the Cathedral of the Madeleine, 331 E. South Temple.

He is survived by his daughter, son-in-law Jon Bird and granddaughter Faye Bird.

Guinney grew up in the restaurant industry, peeling potatoes and busing tables — then doing kitchen prep work — in a coffee shop his father owned. In 1967, he joined the Navy and worked as a cook. After leaving the military in 1971, he worked at Delaney’s seafood in Newport Beach and opened up new restaurants.

A mutual friend introduced him to Williams, who wanted to open a seafood restaurant in downtown Salt Lake City — taking advantage of what was then Western Airlines’ ability to fly in fresh fish each day from Alaska and the West Coast.

" I thought Utah was the perfect place to grow a business," he told The Salt Lake Tribune in 2017. “Salt Lake City was more affordable [than California] and there was this readily available workforce just a few miles away at the University of Utah.”

When Market Street opened, Guinney said, he carried around “a scroungy notebook, covered with stains, with recipes like the clam chowder, the cocktail sauce and tartar sauce."

The popular clam chowder was made with a butter and flour roux, and filled with onions, celery, fresh leeks, sherry and extra-heavy whipping cream.

“It’s one of the finest clam chowders in the United States,” Guinney said. “The consistency is perfect.”

Over the past four decades, Guinney served on numerous committees and community organizations, including leadership positions with the Downtown Alliance, Salt Lake Chamber, and Visit Salt Lake.

Many of Utah’s most successful restaurant owners, chefs and managers learned the business while working for Guinney.

“All of us who enjoy the vibrant hospitality scene downtown owe Tom a debt of gratitude,” leaders of the chamber and alliance said in a joint statement. “It is no coincidence that dozens of Salt Lake’s most vibrant restaurants and bars are clustered around the original Market Street Grill and former New Yorker club. Tom and his partners planted a flag on Market Street that is Salt Lake’s epicurean ground zero.”

Derek Miller, president and CEO of the Salt Lake Chamber, and Dee Brewer, executive director of the Downtown Alliance, wrote that Guinney and his co-founders “raised the bar for dining ambiance, cuisine and particularly for dining service. They trained generations of hospitality workers and leaders that are now working in various industries across the state.”

In addition to their contributions to Salt Lake City’s burgeoning culinary scene, the statement said, “Gastronomy’s adaptive reuse of downtown buildings has preserved many historic gems in our urban core."

Mayor Jackie Biskupski awarded Guinney the Key to the City in 2017 for his contributions to hospitality, philanthropy, the arts, and beautifying and preserving historic parts of the city.

“Like many others,” she said in a statement, “I considered Tom both a friend and a mentor."

While not originally from Salt Lake City, “this was his hometown,” the statement said. “As a successful business owner and community member, he was generous with his time, talents and resources. Kind to friend and stranger alike, and always looking for ways to improve this community through his work.”