[4] Following his mother's death, Simon's father lost the majority of his money during the Great Depression, which harshly impacted his goods store.

He enjoyed early success and invested $7,000 in 1927 in an orange juice bottling plant in Fullerton, California, which was insolvent, and renamed it Val Vita Food Products Company.

As one of the first of his significant corporate moves, Simon sold Val Vita to Hunt's Foods in return for a controlling interest in the combined business.

Uncharacteristically for a food company at the time, he acquired full-page advertisements in Vogue and Life magazines with full-color photos of Hunt's ketchup bottles and tomato sauce cans.

He diversified through acquisition into well known businesses such as McCall's Publishing, the Saturday Review of Literature, Canada Dry Corporation, Max Factor cosmetics, the television production company Talent Associates, and Avis Car Rental, through his holding company Norton Simon Inc. Norton Simon Inc. was formed in 1968 through the merger of Hunt, McCalls, and Canada Dry.

In the 1960s, he spent $6 million on artworks – an inventory of slightly less than 800 objects – and real estate – a building at 18 East 79th Street – from the Duveen Gallery in Manhattan, which specialized in old masters.

[11][12] Scholars including the critic Clement Greenberg and the Metropolitan Museum of Art curator Theodore Rousseau studied the Duveen purchases for Simon and were able to identify numerous misattributions.

Simon ended up selling much of the collection and only kept around 130 objects, primarily paintings, a handful of sculptures, a few porcelains, and a cape purportedly worn by Charles IV of Spain.

In 1972, Simon bought a tenth-century South Indian bronze Nataraja, or dancing Shiva, from New York dealer Ben Heller for $900,000.

[13] He later vehemently denied the quote in the May 13, 1973, edition of the Los Angeles Times, declaring that the work had been legally imported into the United States.

Seeking a permanent home for his collection of over 4,000 objects, in 1972 he welcomed an overture from the financially troubled Pasadena Museum of Modern Art.

He accepted appointments to the University of California Board of Regents, the Carnegie Commission on the Future of Higher Education, the boards of Reed College (in his hometown of Portland), the Los Angeles Music Center, the California School of Professional Psychology at Alliant International University, and the Institute for Advanced Study.

Murphy won renomination, but lost the seat in the general election to the Democrat John V. Tunney, as Republican Ronald Reagan was winning a second term as governor.