The man who invented the Big Mac, considered the quintessential American fast food burger, has died.

Michael “Jim” Delligatti passed away on Nov 28 at his home in a Pittsburgh, Pennsylvania, suburb. He was 98 years old.

Delligatti, a McDonald’s franchisee, came up with the idea in 1967 because he said customers wanted a bigger sandwich. And so he came up with the chain’s signature burger – two all-beef patties, “special sauce”, lettuce, cheese, pickles, onions on a sesame seed bun.

According to AP, his invention was almost rejected by McDonald’s because it was happy with its traditional meals  of hamburgers, cheeseburgers, fries and milkshake were selling well.

He got permission to try his new burger in 1967 and sales jumped 12%, the Times said. Within a few years, McDonald’s was advertising the Big Mac nationwide.

“This wasn’t like discovering the light bulb,” he said. “The bulb was already there. All I did was screw it in the socket.”

The Big Mac

The Big Mac

He said the idea came from rival burger restaurants in the mid-1960s.

After the Big Mac’s invention, the company expanded its menu further, creating an age of new menu items such as the Egg McMuffin (a creation also attributed to Delligatti) and Filet-o-Fish.

But, it was the Big Mac that became a cultural icon. According to MacDonald’s Delligatti never received any royalties for the invention.

In a statement, McDonald’s said Delligatti was a “legendary franchisee” who made a “lasting impression” on the company.

“We will remember Jim as an insightful franchisee, a knowledgeable businessman,” the company said.

McDonald’s says it sells hundreds of millions of the oversized burgers globally, although sales have slowed in recent years as millennials reportedly show less interest in super-sized fast food.

According to Delligatti’s family he went on to own 48 McDonald’s restaurants.

He is survived by his wife Ellie, two children, and a number of grandchildren and great-grandchildren. – Agencies