Marc Andreessen co-invented Mosaic (the first popular graphical web browser) in 1993 as an undergraduate at the University of Illinois, subsequently co-founded Netscape Communications (first major commercial internet company, 1994 IPO), and later co-founded Andreessen Horowitz (a16z) in 2009 with Ben Horowitz — building it into one of Silicon Valley’s most influential VC firms — which launched dedicated crypto investment vehicles beginning in 2018 under Chris Dixon, establishing a16z as one of the most prominent institutional backers of blockchain infrastructure, DeFi protocols, and Web3 consumer applications.
Background
Marc Andreessen was born in 1971 in Cedar Falls, Iowa. He studied computer science at the University of Illinois at Urbana-Champaign. In 1993, he and Eric Bina developed Mosaic — the first web browser with graphical and hyperlink navigation capabilities — at the National Center for Supercomputing Applications (NCSA). Mosaic enabled mass adoption of the World Wide Web.
After graduating, Andreessen co-founded Netscape Communications with Jim Clark in 1994. Netscape Navigator became the dominant early web browser. Netscape’s IPO in August 1995 (at $28/share, closing at $58) is considered the historical starting point of the dot-com era. Netscape was acquired by AOL in 1999 for $4.2 billion.
Andreessen Horowitz (a16z)
Andreessen co-founded a16z in 2009 with Ben Horowitz. The firm differentiated itself from traditional VC by:
- Recruiting operational experts (former CEOs, CMOs, engineers) rather than exclusively financial analysts.
- Building portfolio company support services (executive recruiting, marketing, technical expertise).
- Being highly transparent about investment theses through blog posts and podcasts.
a16z grew to manage over $35 billion across multiple funds by 2024.
Crypto Investment Strategy
Andreessen’s interest in crypto began with Bitcoin. He is notable for writing in 2014 in the New York Times: “Bitcoin represents the first time in history that a digital object is definitively scarce, that it can’t be copied… The technical potential of Bitcoin is profound.”
a16z launched:
- Crypto Fund I ($300M, 2018) — co-led by Chris Dixon and Katie Haun.
- Crypto Fund II ($515M, 2020)
- Crypto Fund III ($2.2B, 2021) — largest dedicated crypto fund at the time.
- Crypto Fund IV ($4.5B, 2022) — raised at/near the bear market start.
Major a16z crypto investments include: Coinbase, Uniswap, Compound, MakerDAO, OpenSea, Axie Infinity (Sky Mavis), dYdX, Solana (early), Optimism, Arbitrum, Farcaster, and dozens more.
The Techno-Optimist Manifesto (2023)
In October 2023, Andreessen published “The Techno-Optimist Manifesto” — a sweeping argument for technology and markets as the primary forces for human flourishing, explicitly rejecting “Luddite” regulatory and precautionary approaches. The essay was widely read and debated; critics argued it was ideological rationalization for minimizing tech regulation, while supporters saw it as a principled defense of technological progress.
Key Essays
- “Why Software Is Eating the World” (2011) — Widely-cited essay predicting that software and internet companies would displace incumbents across every industry.
- “Bitcoin and What It Means” (2014) — Early institutional-quality Bitcoin advocacy in mainstream media (New York Times).
- “Techno-Optimist Manifesto” (2023) — Comprehensive technology advocacy document.
Key Dates
- 1993 — Co-creates Mosaic web browser at UIUC.
- 1994 — Co-founds Netscape Communications.
- 1995 — Netscape IPO; dot-com era begins.
- 2009 — Co-founds Andreessen Horowitz (a16z) with Ben Horowitz.
- 2014 — Publishes Bitcoin advocacy piece in New York Times.
- 2018 — a16z launches Crypto Fund I ($300M).
- 2021 — a16z Crypto Fund III ($2.2B) — largest dedicated crypto fund at the time.
- October 2023 — Publishes “The Techno-Optimist Manifesto.”
Common Misconceptions
- “Andreessen invented the internet.” — Andreessen invented Mosaic, the first popular graphical web browser. The internet and World Wide Web protocols were developed earlier by others (Tim Berners-Lee for HTTP/HTML, DARPA for internet protocols).
- “a16z makes crypto protocol decisions.” — a16z is a financial investor; it does not control the protocols it invests in. Protocol governance is determined by decentralized communities and token holders.
Last updated: 2026-04