In April 2021, the Midwestern Higher Education Compact (MHEC) convened a working group of institution, state, and national leaders to help advise its efforts to develop a set of principles to improve consistency and reliability in the field for measuring cost savings and the return on investment (ROI) of open education resources (OER). The result of this work was the report, "Toward Convergence: Creating Clarity to Drive More Consistency in Understanding the Benefits and Costs of OER." The report outlined six principles to help define efforts to identify savings and ROI from OER investments. Following on this work, MHEC and its partners determined to explore more about course marking of OER in U.S.-based postsecondary institutions via a landscape analysis survey. The survey included questions related to the course marking process, validation of course marking data, technology, motivations for marking of courses, use of course marking data, and opportunities and challenges encountered by institutions and systems when marking courses. This report is an analysis of the survey. [This report was prepared in partnership with the National Consortium for Open Education Resources (NCOER).]