Using an input output “I-O” approach to estimating the economic impact of academic licensing, and summing over the 15 years of available data for academic U.S. AUTM Survey respondents, the total contribution of these academic licensors to gross industry output ranges from $199B to $836B, in 2005 $US Dollars; contributions to GDP range from $86B to $338B, in 2005 $US Dollars. Estimates of the total number of person years of employment supported by U.S. universities’ and hospitals’ and research institutes’ licensed-product sales range from 900,000 to over 3 million over the 15 year period. An explanation of the I-O approach is provided, and the assumptions used and the potential effects of the assumptions on the estimates are discussed. The rationale for including impacts from hospital and research institutes together with those of universities is presented. Better information on i) royalty rates and royalty bases, ii) where in the world the academic licensors produce their products and where the intermediate inputs used to produce their products are produced, iii) whether the royalty generating products are manufactured items or services, and iv) whether the purchaser is the final purchaser will lead to more accurate estimates.