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Through a few friends I know who work as recruiters at some temporary agencies, for certain contracts the department was told to edit resumes (and heighten them so the pay rate is a few dollars higher). They noticed small edits to a few resumes submitted a day or two before being told (i.e. changing percentages from 60% to 75%, or 50,000 to 150,000, etc.) that would make the candidate appear to achieve outstanding results at their past/current employer. They said most of the staff treated the directive like common place (i.e. most were already doing it/have done it before). This made me worry as I do apply at some staffing companies, but I have not heard of this happening (but then again, who would know).
As I have been applying, I have my resume in Word format (.docx), and I have wonder if it would be wise to make it read-only to prevent those kind of changes from hiring managers or anybody (not that they would, but just to be safe). Would this be frowned upon or looked down upon by hiring managers? Would they assume incompetence or "sketchiness" if a document was locked for editing? The only reason I can think so is if someone just wanted to highlight or bold features in the resume for review upon interviewing the candidate.