In recent years, the United States Patent and Trademark Office has systematically been engaging the legal community with inventor assistance beyond the agency’s usual business of examining applications for patents and trademarks. The purpose of the USPTO’s effort has been to support innovators who are constrained by a lack of resources to pay for patent counsel necessary to protect the full scope of their inventions. This Article describes the brief history, flexible structure, and ongoing growth of that effort, embodied in the USPTO Patent Pro Bono Program. The Patent Pro Bono Program is a national network coordinated by the USPTO to connect inventors and small businesses with registered patent attorneys and agents to assist in the filing and prosecution of patent applications for free. At the regional level, a broad array of non-profit organizations, bar associations, community economic development organizations, and institutions of higher education support the USPTO in matching low-income inventors with experienced patent professionals. At the individual level, volunteer patent attorneys and their inventor clients engage in the usual back-and-forth of the USPTO examination process, seeking patent protection as a way to enter or advance in the marketplace. In short, the program is a structural effort to bring independent inventors and startups the same opportunity of investment and economic competition that large and established incumbents enjoy.