Our project had three research questions. In defense contracting in the United States, over the period 2000 through 2019, at the industry and firm level,A. Did free cash flow (FCF) increase or decrease over time?B. For what was FCF being used, and did that change over time?C. Was there a relationship between FCF and independent research and development (IR&D)?Our research sponsors specifically directed that we use a particular sample: at least 25 firms which earned at least 25 percent of their 2019 revenue from the Departments of Defense and Homeland Security, and the National Aeronautics and Space Administration. From these restrictions, we developed an unbalanced panel of 29 qualifying firms. For informing policy towards a range of defense contractors of different sizes, in some tests, we normalized FCF and its uses as margins (dividing by revenue) to avoid outsized effects from the largest firms. To avoid endogeneity, we modified FCF with the addition of IR&D spending for those models involving IR&D as a dependent variable. Across the time period in question, with this sample, we obtained the following results:A. Across the industry, FCF did not show a statistically significant increase. FCF margins gradually increased, but slightly, with considerable variation. The effect depends highly on an outlier and the last two years of the time series.B. FCF margins have been negatively related to spending on acquisitions, scaled by revenue.C. Modified FCF (with IR&D added back, denoted FCF*) showed no statistically significant relationships with IR&D spending, in levels or margins, in current or following periods.These results have changed somewhat from those of our initial report of September 2021, after testing for autocorrelation, heteroskedasticity, and cross-sectional dependence required application of robust standard errors. Details are available in our data and results files, conveyed separately.The findings of the non-dependence of IR&D spending on FCF* are consistent with classic finance theory, specifically the Modigliani-Miller Theorem. The finding on acquisitions is not, and was indeed unexpected. We offer a possible theoretical explanation, and recommend further research