Since its early days, California has always attracted people from all over the world seeking fame and fortune. Roughly 25% of the nation's billionaires call the Golden State home, and a significant number of them live in the Los Angeles area. From influential music moguls to innovative entrepreneurs and doctors, the billionaires at the top of the list are nearly as diverse as the city itself.

1. Elon Musk

After initially building his fortune as a co-founder of PayPal, Elon Musk is now involved in projects ranging from space travel to disrupting the transportation industry. He is worth an estimated $22.3 billion, according to Forbes. One of his companies, Tesla is bringing luxury electric cars to the mass-market, although it continues to struggle to make a profit. Another one, SpaceX is aiming to revolutionize transportation in space. 

Musk also is the chairman and principal owner of SolarCity, a solar panel design and installation company that provides solar power systems to homeowners and businesses. One of Musk's most innovative ideas is the Hyperloop, a high-speed transportation system that would send travelers between Los Angeles and San Francisco in less than 30 minutes through a system of tubes.

2. David Geffen

David Geffen built a music industry empire by helping to launch the careers of some of the most iconic bands in the world, such as The Eagles, Aerosmith, Guns N' Roses and Nirvana. A college dropout, Geffen founded Geffen Records and Asylum Records, selling the latter to MCA for $550 million in 1990.

He then started the DreamWorks SKG movie studios with Steven Spielberg and Jeffrey Katzenberg, and he now has a net worth of $8.1 billion, according to Forbes estimates. For his influence and success in the industry, Geffen was inducted into the Rock and Roll Hall of Fame in 2010.

3. Patrick Soon-Shiong

In a city known for glitz and glamour, one of the richest people in Los Angeles is an unassuming doctor most people have never heard of. Patrick Soon-Shiong, also known as Dr. Pat, has built a fortune redefining cancer treatments and is on a mission to find a cure to eradicate the disease. Originally a surgeon, Soon-Shiong turned his attention to pharmaceuticals, founding both Abraxis and American Pharmaceutical Partners, and later selling them for a combined $9.1 billion.

Soon-Shiong's newest company, NantKwest, develops cancer drugs and algorithms that can analyze a human genome in seconds, drastically improving the effectiveness of many cancer treatments. The company’s $200 million initial public offering (IPO) in 2015 valued NantKwest at more than $2.5 billion. His biotech company, NantHealth, went public in 2016.

Soon-Shiong is also a part-owner of the Los Angeles Lakers and has an estimated net worth of $9 billion, according to Forbes. He acquired the Los Angeles Times and The San Diego Union-Tribune in June 2018 for a reported $500 million. 

4. Eli Broad

With an estimated net worth of $6.7 billion, according to Forbes, Eli Broad is one of the richest men in Los Angeles. He is also among the nation's most generous philanthropists, supporting education reform, medical research and the arts. He is responsible for building two Fortune 500 companies in different industries. He founded KB Home in 1957 and turned it into one of the nation's largest homebuilders, with a focus on affordable housing. He later bought Sun Life Insurance in 1971 and sold it to AIG for $18 billion in 1998.

Having turned his attention to the arts, Broad is a major art collector and spent $340 million to build his own art museum. The Broad, which opened in 2015, displays his personal collection, which is valued in the billions. The museum in downtown Los Angeles features thousands of works and offers free admission, paid for by a grant provided by Broad and his wife.