Key Takeaways
- • Marc Andreessen runs Andreessen Horowitz, a Silicon Valley venture firm whose portfolio includes Instagram, Oculus VR and GitHub, according to his Forbes profile.
- • Andreessen cofounded Netscape, which AOL acquired in 1998 for $4.2 billion in stock, and cofounded Loudcloud (later Opsware), which Hewlett-Packard bought for $1.6 billion in 2007.
- • His largest reported investment win was as a seed investor in Facebook.
- • Andreessen's a16z raised $300 million in June 2018 for its first crypto-focused fund, co-led by Chris Dixon and Katie Haun.
- • Forbes lists him as a Midas List investor and estimates his net worth at $1.9 billion as of June 2026.
Summary
Marc Andreessen is a Silicon Valley venture capitalist and technology pioneer who runs Andreessen Horowitz, commonly referred to as a16z. According to Forbes, the firm's successful bets include Instagram, Oculus VR and GitHub. Andreessen's earliest prominence came from cofounding the web browser company Netscape, which AOL bought in 1998 for $4.2 billion in stock. He also co-created the Mosaic Internet browser while still at university, developing it at the National Center for Supercomputing Applications in 1993.
Andreessen's largest investment success, per the Forbes profile, was as a seed investor in Facebook. He also cofounded Loudcloud, a data center software company that was later renamed Opsware and sold to Hewlett-Packard for $1.6 billion in 2007. Together with Ben Horowitz, he worked at Netscape before building these later ventures.
In June 2018, a16z raised $300 million for its first crypto-focused fund, co-led by Chris Dixon and the firm's first female general partner, Katie Haun. Publisher context describes a16z as managing more than $90 billion in assets under management. Forbes ranks Andreessen at #2177 on its 2026 Billionaires list and estimates his net worth at $1.9 billion as of June 2026. He has also been an advisor to Donald Trump since 2024. Forbes profiles him as self-made, based in Menlo Park, California, and notes that his wife Laura is the daughter of Silicon Valley real estate developer John Arrillaga.
Andreessen's largest investment success, per the Forbes profile, was as a seed investor in Facebook. He also cofounded Loudcloud, a data center software company that was later renamed Opsware and sold to Hewlett-Packard for $1.6 billion in 2007. Together with Ben Horowitz, he worked at Netscape before building these later ventures.
In June 2018, a16z raised $300 million for its first crypto-focused fund, co-led by Chris Dixon and the firm's first female general partner, Katie Haun. Publisher context describes a16z as managing more than $90 billion in assets under management. Forbes ranks Andreessen at #2177 on its 2026 Billionaires list and estimates his net worth at $1.9 billion as of June 2026. He has also been an advisor to Donald Trump since 2024. Forbes profiles him as self-made, based in Menlo Park, California, and notes that his wife Laura is the daughter of Silicon Valley real estate developer John Arrillaga.
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