Andreessen Horowitz

Overview

Andreessen Horowitz (a16z) is a venture capital firm that invests in early-stage startups and growth companies across sectors including healthcare, consumer, cryptocurrency, gaming, fintech, education, and enterprise software.¹ As of July 2025, it ranks first among venture capital firms by assets under management at $46 billion.¹ The firm is known for its founders' prior success as 'super angel' investors and high-profile investments like Skype.

History

Andreessen Horowitz was founded in 2009 by Marc Andreessen and Ben Horowitz, who had previously invested in 45 startups including Twitter between 2006 and 2010.¹ Its first investments included Apptio and Skype in 2009, with the latter sold to Microsoft for $8.5 billion in 2011.¹ By 2012, it was described as the most powerful VC firm in Silicon Valley, and as of 2025, it leads in assets under management.¹

Notable Products

• Skype investment - Early investment in 2009 that resulted in an $8.5 billion sale to Microsoft in 2011.
• Apptio investment - First investment in 2009 in business management SaaS developer.
• Flow investment - Investment in real estate startup founded by WeWork's Adam Neumann, noted as controversial.

Reputation

Andreessen Horowitz is perceived as one of the most powerful and well-known VC firms, with a portfolio that bolsters its reputation among professionals.¹⁴ Founders are drawn to its outspoken and controversial approach, which Marc Andreessen views as a competitive advantage.² It faces criticism for publicity mishaps and controversial hires or investments.²³ Employee reviews on Glassdoor show 63% would recommend working there.⁵