"As production comes to depend more on intangible productive assets, the location of production by multinational firms becomes increasingly ambiguous. The reason is that, within the firm, these assets have no clear geographical location, but only a nominal location determined by the firm's tax...

This paper advances a new technique for identifying, delineating, and analyzing microgeographies. It applies this technique to locate and measure agglomerations of high-growth, high-tech (HGHT) startup activity within 205 U.S. cities. Using data from 1995 to 2018 on venture-backed companies, I...