Marc Andreessen

Marc Andreessen is a technology entrepreneur and venture capitalist operating in Silicon Valley. In 1993, he co-created Mosaic, one of the first graphic web browsers in history, which greatly accelerated the process by which the general public became users of the World Wide Web. Before Mosaic, there were about 50 websites in existence; a year following Mosaic’s release, there were roughly 10,000 websites. 1 Andreessen is a co-founder, and as of 2026, was a general partner of venture capital firm Andreessen Horowitz (also known as a16z). 2 As of August 2026, Forbes estimated Andreessen’s net worth to be $1.9 billion. 3

Read More

At-A-Glance

Nationality:

American

Born:

July 9, 1971

Occupation:

Technology Entrepreneur

Contents

    Andreessen is active on social media and often engages in political messaging. In the 2024 presidential election, he supported Donald Trump, and went on to serve as one of his advisors during the second Trump administration. 4

    Ahead of the 2026 midterms, Andreessen, through his firm Andreessen Horowitz, poured $25 million into Leading the Future PAC, a sister group to the pro-AI advocacy organization Build American AI. 5

    Career

    Marc Andreessen is a technology entrepreneur and venture capitalist operating in Silicon Valley. Andreessen attended University of Illinois Urbana-Champaign for an undergraduate degree in computer science. During this time, he interned with IBM and worked as a programmer at the National Center for Supercomputing Applications (NCSA) at the University of Illinois, where he became familiar with the Internet. 6 7

    In 1993, while still a college student, Andreessen and Eric Bina created Mosaic, one of the first graphic web browsers in history, which greatly accelerated the process by which the general public became users of the World Wide Web. The Web, created by British computer scientist Tim Berners-Lee, was at that time tremendously difficult to use for anyone without adept programming skills; additionally, its text-only layout had been described as “boring” compared to the “visually exciting,” “magazine”-like experience Mosaic introduced. In Andreessen’s words, Mosaic software “spread like a virus,” triggering a 342,000 percent increase in web traffic within one year. At the start of 1993, there were about 50 websites in existence, while a year later there were roughly 10,000. 1 8

    In December 1993, Andreessen graduated from the University of Illinois Urbana-Champaign. Andreessen went on to found Mosaic Communications, an Internet software company. He later changed its name to “Netscape Communications,” with its major product being the web browser Netscape Navigator. Netscape and its umbrella of products showed marked improvements in speed and design over Mosaic, particularly in its integration of financial transaction features, and it is considered to have been the first successful commercial browser of its kind. Netscape was acquired by AOL in 1999 for $4.3 billion, with Andreessen taking the role of chief technical officer. 9 10 11 12

    In 1998, Andreessen and colleagues Ben Horowitz, Tim Howes, and In Sik Rhee founded Loudcloud, a software services company for e-commerce companies. In 2003, it changed its name to “Opsware,” and Andreessen became the firm’s chairman. In 2007, the company was sold to Hewlett-Packard for $1.6 billion. 13 14

    Andreessen’s largest financial success came with his decision to become a seed investor of Facebook. As of 2026, he continued to sit on the board of Facebook’s parent company, Meta. 3 15

    As of 2026, Andreessen also sat on the boards of Applied Intuition, Carta, Coinbase, Dialpad, Flow, Golden, Honor, OpenGov, Samsara, Simple Things, and TipTop Labs, all of which were in a16z’s investment portfolio.

    Andreessen Horowitz

    Andreessen is a co-founder, and as of 2026, was a general partner of venture capital firm Andreessen Horowitz (a16z). 2

    Andreessen Horowitz’s major investments include Instagram, Oculus VR, GitHub, and Coinbase. 3 16

    Coinbase

    Andreessen’s venture capital firm Andreessen Horowitz was one of the early investors in Coinbase, a digital cryptocurrency exchange platform. a16z and its “family of funds” invested in Coinbase on eight separate occasions between 2013 and 2020. a16z’s staffers and leaders have a close relationship with Coinbase’s founders. As of 2026, Andreessen sat on Coinbase’s board alongside co-founders Brian Armstrong and Fred Ehrsam. 16 17 18

    Political Funding

    During the 2024 Presidential election, Andreessen contributed over $5 million to organizations that supported the campaign of then-former President Donald Trump. 19

    As of April 2026, Andreessen, through his firm Andreessen Horowitz, had poured $25 million into Leading the Future PAC, a sister group to the pro-AI advocacy organization Build American AI, in advance of the 2026 midterm elections. 5

    As of August 2026, Andreessen Horowitz or people associated with the firm had contributed over $47 million to the pro-cryptocurrency super PAC network Fairshake since November 2024, as well as $12 million to MAGA Inc., the super PAC of President Trump. Andreessen reportedly donated $900,000 of his personal wealth to the Republican National Committee in March 2026. The New York Times described Andreessen Horowitz as the number one political donor in the 2026 midterms as of May 2026, surpassing historic donors such as George Soros, Elon Musk, and Jeffrey Yass. 20

    Political Allegiances

    Marc Andreessen has been described as a former longtime Democrat who shifted his allegiance to the right-of-center in the United States, particularly in the run up to the second Trump administration. In the 2024 presidential election, he supported the campaign of then-former President Donald Trump, and went on to serve as one of his advisors during the second Trump administration. 19 4

    Andreessen volunteered to help with the early stages of the Trump administration’s Department of Government Efficiency (DOGE), which at the time was being led by Tesla CEO Elon Musk. In January 2025, Andreessen jokingly referred to himself as an “unpaid intern” of DOGE, and in an interview with the right-of-center Hoover Institution said it was a priority of his to curb the number of federal employees working remotely. 19 21

    Andreessen is active on social media and often engages in political messaging. In October 2023, Andreessen released the Techno-Optimist Manifesto, an essay in which he extolled technological growth and free-market economics while sharply criticizing socialist movements, such as “degrowth” ideology. 22

    Political observers alleged that Andreessen’s positive relationship with President Trump contributed to the president’s decision to drastically curtail the operations of the Consumer Financial Protection Bureau (CFPB), a regulatory federal agency that Andreessen had publicly condemned as a weapon that existed to “terrorize finance, terrorize financial institutions, prevent fintech, prevent new competition, new startups that want to compete with the big banks.” 19

    Contact InfluenceWatch to report errors, suggest edits, or provide tips for additional profiles.

    Contact Us

    Mentioned in this Article

    References

    1. Keen, Andrew. The Internet Is Not the Answer. Open Road + Grove/Atlantic, 2015. Chapter 2. https://books.google.com/books?id=D3UkBQAAQBAJ&pg=PT17#v=onepage&q&f=false.
    2. “Marc Andreessen.” A16z. Accessed August 11, 2026. https://a16z.com/author/marc-andreessen/.
    3. “Marc Andreessen.” Forbes, August 11, 2026. Accessed August 11, 2026. https://www.forbes.com/profile/marc-andreessen/.
    4. Tiku, Nitasha. “Tech billionaire Trump adviser Marc Andreessen says universities will ‘pay the price’ for DEI.” The Washington Post, July 12, 2025. Accessed August 11, 2026. https://www.washingtonpost.com/technology/2025/07/12/marc-andreessen-private-chat-universities-diversity/.
    5. Birnbaum, Emily; Allison, Bill. “Andreessen, Horowitz Boost AI Super PAC to Over $50 Million.” Bloomberg, April 15, 2026. Accessed July 6, 2026. https://www.bloomberg.com/news/articles/2026-04-15/andreessen-horowitz-boost-ai-super-pac-cash-to-over-50-million.
    6. “Marc L. Andreessen.” University of Illinois Urbana-Champaign. https://grainger.illinois.edu/alumni/hall-of-fame/marc-andreessen.
    7. Tsotsis, Alexia. “Marc Andreessen On The Future Of Enterprise.” TechCrunch, January 27, 2013. Accessed August 19, 2026. https://techcrunch.com/2013/01/27/marc-andreessen-on-the-future-of-the-enterprise/.
    8. “April 22, 1993: Mosaic Browser Lights Up Web With Color, Creativity.” WIRED, April 22, 2010. Accessed August 11, 2026. https://www.wired.com/2010/04/0422mosaic-web-browser/.
    9. “Marc Andreessen.” Centre for Computing History. Accessed August 11, 2026. https://www.computinghistory.org.uk/det/1789/Marc-Andreessen/.
    10. The Oxford Handbook of the Digital Economy. Edited by Martin Peitz and Joel Waldfogel. Oxford University Press, July 9, 2012. Accessed August 11, 2026. Page 8. https://books.google.com/books?id=GFm-5WuYfYAC&pg=PA8#v=onepage&q&f=false.
    11. Bigdoli, Hossein. Electronic Commerce: Principles and Practice. Academic Press, 2002. Accessed August 11, 2026. Page 31. https://books.google.com/books?id=_HnkswLHMC4C&pg=PA31#v=onepage&q&f=false.
    12. “AOL Names Andreessen CTO.” Reuters via WIRED, February 18, 1999. Accessed August 11, 2026. https://www.wired.com/1999/02/aol-names-andreessen-cto/.
    13. Venkat, Girish. “Loudcloud: Early light on cloud computing.” CNET, March 23, 2009. Accessed August 11, 2026. https://web.archive.org/web/20130330034003/http://news.cnet.com/8301-1001_3-10202058-92.html.
    14. Martens, China. “HP Buying Opsware in $1.6 Billion Deal.” PC World, July 24, 2007. Accessed August 11, 2026. https://web.archive.org/web/20210308174420/https://www.pcworld.com/article/134946/article.html.
    15. “Leadership and Governance.” Meta. Accessed August 11, 2026. https://investor.atmeta.com/leadership-and-governance/.
    16. Haun, Katie. “Coinbase Direct Listing.” Andreessen Horowitz, April 14, 2021. Accessed July 10, 2026. https://a16z.com/coinbase-direct-listing/.
    17. “About.” Coinbase. Accessed July 10, 2026. https://www.coinbase.com/about.
    18. “Global Advisory Council.” Coinbase. Accessed July 10, 2026. https://investor.coinbase.com/governance/Global-Advisory-Council/.
    19. Pearson, Jake. “Tech Billionaire Marc Andreessen Bet Big on Trump. It’s Paying Off for Silicon Valley.” ProPublica, November 5, 2025. Accessed August 17, 2026. https://www.propublica.org/article/trump-cfpb-marc-andreessen-silicon-valley.
    20. Schleifer, Theodore. “Andreessen Horowitz Is Spending on Politics Like No Other.” The New York Times, May 13, 2026. Accessed August 17, 2026. https://www.nytimes.com/2026/05/13/technology/andreessen-horowitz-politics.html.
    21. Redmond, Nora. “DOGE’s ‘unpaid intern’ Marc Andreessen says DC is a ghost town, and bringing government workers back is a top priority.” Business Insider, January 17, 2025. Accessed August 17, 2026. https://www.businessinsider.com/marc-andreessen-doge-rto-staff-office-ghost-town-washington-dc-2025-1.
    22. Andreessen, Marc. “The Techno-Optimist Manifesto.” A16z, October 16, 2023. Accessed August 17, 2026. https://a16z.com/the-techno-optimist-manifesto/.