RPX, Defensive Patent Firm, Goes from Zero to $160M IPO in Less than Three Years

As examples of ultra-fast growth in the tech world, people like to talk about Groupon and Zynga. While they are phenomenal success stories, neither of those companies is publicly traded yet—nor, for that matter, are Twitter or Facebook. Well, how about a different kind of tech company that started in 2008 and held its IPO today? That would be RPX, a San Francisco-based “defensive patent aggregation” company with Seattle roots, whose venture investors are in Boston, London, and the Bay Area. RPX filed for an initial public offering in January and says today it has raised $159.6 million in an offering underwritten by Goldman Sachs and Barclays Capital. The firm sold about 8.4 million shares at $19 per share, with trading to begin on the Nasdaq today. (Pricing above the anticipated range of $16-$18 was announced this morning.)