Introduction In this paper we present an overview of a series of studies pursued at the NBER during the last decade which used patent statistics to study different aspects of the economics of technological change. It consists of five substantive sections: a description of our firm level data; a report on the relationship between R&D expenditures and the level of patenting; a report on the relationship between patents, the stock market value of firms, and their R&D expenditures; a summary of work on the estimation of the value of patent rights based on patent renewal data; and a description of the use of patent data to estimate the importance of R&D spillovers. A brief set of conclusions closes the paper. The NBER R&D data base and the growth of US firms in the 1970s A major achievement of the NBER project has been the development and construction of a large data set covering the economic and technological performance of most publicly traded US manufacturing companies from the early 1960s through the early 1980s. It is the result of a detailed match of publicly available sales, employment, investment, R&D, and balance sheet information from the Compustat tapes (based on company 10–K filings with the SEC) with data acquired from the US Patent Office on patents issued to all organizations between 1969 and 1982.