Venture capital firm Andreessen Horowitz said Tuesday that it raised $7.2 billion across five different funds, a sign of optimism in the tech startup world, which has seen a dearth of significant exits over the past two years. “This marks an important milestone for us,” Ben Horowitz, who co-founded the firm with Marc Andreessen in 2009, wrote in a blog post. The biggest chunk of new funding is in Andreessen Horowitz’s growth fund, which reeled in $3.75 billion. That money gets invested in later-stage companies that are viewed as closer to going public, or capital-intensive businesses that require big checks. Horowitz ... (full story)