Strengthening Agency Management and Oversight of Software Assets Act This bill addresses software asset management practices by federal agencies. The bill requires each agency to complete a comprehensive assessment of the software entitlements and software inventories of the agency and submit the assessment to the head of the agency, the Office of Management and Budget (OMB), the General Services Administration, the Government Accountability Office (GAO), and Congress. Each agency must use the information developed pursuant to the assessment to develop a plan for the agency to (1) consolidate software licenses of the agency; and (2) adopt enterprise license agreements across the agency by type or category of software in order to improve the performance of, and reduce unnecessary costs across, the agency. The OMB must submit to Congress a strategy that includes proposals to support the adoption of governmentwide enterprise licenses for software entitlements identified through the assessments and plans; opportunities to leverage government procurement policies and practices to increase interoperability of software entitlements acquired and deployed to reduce costs and improve performance; the incorporation of data on spending by agencies on, the performance of, and management by agencies of software entitlements as part of certain required information; and where applicable, directions to agencies to examine options and relevant criteria for transitioning to open-source software. The GAO must report on governmentwide trends, comparisons among agencies, and other analyses of plans and strategy.