Patent pools are a unique form of research and development (R&D) consortium in which licensor firms (technology sellers) bundle together essential patents for licensing out to each other and to third-party licensee firms (technology buyers). Over the last hundred years, governments rarely approved patent pools because of concerns about excessive or inappropriate knowledge sharing among participating firms and the possibility of anti-competitive activity. However, in recent years, regulatory authorities in the United States and Europe enacted policy changes and sanctioned the formation of patent pools in a variety of industries that are economically and technologically important. In this study, we utilize the formation of patent pools as a natural experiment for testing a much debated proposition in organizational research ––– market-based versus network- based explanations for technology selection by firms. For the patents which technology sellers seek to license out to technology buyers, we posit that both the market value of the invention and the network position of the inventor impact the selection of patents for bundling in a patent pool. We conduct empirical analyses utilizing data from multiple patent pools formed within the same timeframe and within the same industry (optical discs). We find that market and network factors reinforce, rather than counteract each other in driving which patents are deemed essential and bundled together in a pool. Our findings have strategic implications for firm-level innovation by technology sellers and buyers as well as policy implications for government regulators.