Described is the selective exclusion of content returned in a requested screen capture operation, wherein exclusion may be determined by a window category and the requesting application program. For example, a magnification program will not received content captured from its own layered window or from any other layered magnification windows. A registration mechanism obtains and maintains a window handle for any window registered for exclusion. A screen capture mechanism uses the information to determine whether to exclude the content of windows when returning the captured screen content. Exclusion may be accomplished by enumerating areas that are not covered by any layered window and copying those areas to a screen representation buffer or the like, and separately enumerating areas that are covered by at least one layered window. A covered area is only copied to the screen representation when it does not correspond to an excluded window.