One of the most common activities of dissertation supervisors working in undergraduate programs is to provide written feedback to students'drafts. The present study describes a corpus of 1061 Genre-Oriented Written Comments (GOWC) provided by 12 faculty to 3 drafts submitted by their respective students during one semester. The research is part of the FONDECYT Project 1140360 and is a descriptive case study with a quantitative approach. Participants belong to 4 different teaching degrees from two Chilean universities in the city of Conception. The analysis of the GOWCs shows that supervisors offer feedback for the text to progressively approximate the generic features of academic dissertations. The text must present the prototypical sections, distinguish between the voices and the authors, consider the system of activity and be discursively appropriate.