This article has been reviewed according to Science X's editorial process and policies . Editors have highlighted the following attributes while ensuring the content's credibility: Credit: Unsplash/CC0 Public Domain Since the dawn of the new millennium, there have been at most several thousand startup tech companies across the U.S. that have achieved unicorn status—crossing the $1 billion valuation. Eric Lefkofsky, 55, the Chicago-based serial entrepreneur best known for co-founding online daily deals si ...