Elon Musk is a busy man, and it’s a perpetual mystery how he splits time across the many companies where he serves one or more leadership roles. The world’s richest man (currently worth $225 billion) once said he regularly worked 80 to 100 hours a week—and that was in 2018, well before Tesla (TSLA) and SpaceX expanded into new businesses and Musk added Twitter under his belt.
“My days are very long and complicated, as you might imagine…The time management is extremely difficult,” Musk said at a leadership event in May. He said he generally divides his schedule “so it’s predominantly one company on one day.”
Musk’s companies span automotive, aerospace, solar energy, infrastructure and artificial intelligence. These seemingly unrelated industries all serve the same goal: get humanity to Mars and, in the meantime, create “a sustainable energy civilization” on Earth, Musk has said. And with the acquisition of Twitter last year, he has embarked on an additional mission to create a digital public town square where everyone can freely express their views.
Here is a (running) list of every company controlled by Elon Musk, what they do, and the key people who help Musk run them:
Tesla: electric vehicles, software
- Founded in: 2003
- Number of employees: about 12,800
- Market value: $660 billion
Tesla is the only publicly traded company in Musk’s vast portfolio. It employed roughly 12,800 people as of 2022 and is currently valued at $660 billion, ranking it among the world’s 10 largest public companies by market cap. Tesla makes electric cars and various software packages that add driving features to those cars.
In recent years, the company has expanded into more businesses, including auto insurance, EV batteries and solar panels—through the acquisition of SolarCity, a company founded by Musk’s cousins, in 2016. Musk is Tesla’s CEO and the company’s largest shareholder. However, his increasingly divided attention to other businesses has drawn criticism from key investors questioning his commitment to the company.
Read More: Where Will Elon Musk Build Tesla’s Next Gigafactory?
SpaceX: Rockets, satellites
- Founded in: 2002
- Number of employees: more than 13,000
- Market value: $150 billion
SpaceX sits at the center of Musk’s ambition to colonize Mars. He serves as not only the company’s CEO, but also its chief technology officer and chief designer, deeply involved in every aspect of the design and engineering of SpaceX rockets and satellites. Besides those two functions, Musk has said he leaves the day-to-day operations largely to Gwynne Shotwell, who acts as SpaceX’s president and chief operating officer. Shotwell joined SpaceX in 2002 to lead business development, and was promoted to president in 2008 after scoring a major NASA contract.
Read More: Is Elon Musk a Real Rocket Scientist? His Many Titles at SpaceX Explained.
The Boring Company: tunneling
- Founded in: 2016
- Number of employees: fewer than 200
- Market value: $5.7 billion
The Boring Co. is a tunneling company born partly out of Musk’s frustration with the traffic congestion in Los Angeles. Its main business is digging tunnels to facilitate a future high-speed transportation mode known as “hyperloop.” But for now, the Boring tunnels are just regular tunnels for passenger vehicles to drive through. The company has built three tunnels so far, including a 1.7-mile-long passageway underneath the Las Vegas Convention Center explicitly designed for Tesla cars. The Boring Co. was most recently valued at $5.7 billion after closing a series C round in April 2022.
Read More: Elon Musk’s Boring Company Is Not Groundbreaking Tech, Says Tunnel Expert
Neuralink: biotech, robotics
- Founded in: 2016
- Number of employees: about 300
- Market value: $5 billion
Neuralink is developing an artificial intelligence chip that can be implanted in human brains by a robot surgeon. Musk serves as an executive officer at the company, while Jared Birchall, Musk’s money manager, acts as a director, according to an SEC filing in August 2021. Other key executives include venture capitalist Shivon Zilis, the mother of two of Musk’s children.
Musk has hosted several Neuralink product demos where the company’s brain chips were seen working in pigs and monkeys. In May, Neuralink received the Food and Drug Administration’s approval to test its brain chips in humans.
Read More: Neuralink’s Monkey Experiment Raises Questions From Scientists and Tech Ethicist
X (formerly Twitter): social media
- Acquired in: 2022
- Number of employees: about 1,300
- Market value: $20 billion
Musk loved using Twitter so much that he eventually bought the company last year and paid a considerable premium. Despite having little experience running a social media company, Musk made dramatic changes to Twitter since becoming its owner, including firing more than 80 percent of its employees, officially changing its name, and revamping its content policy and subscriptions. To make his workload more manageable, Musk appointed former NBCU ad exec Linda Yaccarino as the company’s CEO in May.
But business isn’t going particularly well. In March, Musk admitted Twitter had lost about half of its value since he paid $44 billion for it last October.
Read More: Twitter’s Advertising Offerings Were Lacking Even Before Elon Musk Came Along
xAI: artificial intelligence
- Founded in: 2023
- Number of employees: 12
- Market value: unknown
xAI is Musk’s latest venture aimed at creating an alternative product to OpenAI’s ChatGPT and similar A.I. chatbots. He argued the world needs a new A.I. chatbot because Big Tech companies like Google (GOOGL) and Microsoft (MSFT) are too focused on profitability and don’t care enough about A.I. safety.
xAI was incorporated in Nevada in March. In a state filing, Musk’s money manager Jared Birchall was again listed, this time as a secretary, while Musk himself was listed as the company’s sole director.
Almost all of xAI’s founding members are former engineers and scientists at OpenAI, DeepMind, Google, Microsoft and Tesla. According to its website, xAI’s goal is “to understand the true nature of the universe.”
Real More: Meet the 12-Man Founding Team of xAI