“…As discussed earlier, MAR externalities suggest that industrial clustering contributes to knowledge spillovers and therefore to knowledge spillover entrepreneurship. Challenging this traditional thinking, Klepper and his collaborators (Buenstorf & Klepper, 2009;Golman & Klepper, 2016;Klepper, 2001Klepper, , 2007Klepper, , 2010Klepper, , 2011 argued that it is localized spin-off activity, and not benefits from agglomeration economies, that leads to industrial clustering. Their investigations on different industries (such as semiconductors in Silicon Valley, tires in Akron, and automobiles in Detroit) revealed similar patterns of industrial clustering: One superior firm started somewhere, often serendipitously, and spin-offs from this firm grew the industry into a strong cluster in the same place.…”