US Patent 9535883 Modifying native document comments in a preview

A document preview system provides previews of a native document to client devices. The previews include comments associated with native objects in the native document. The document preview system identifies bounding areas in the preview associated with the native objects, which may be identified by the rendering markers applied to the native document prior to rendering. Using the bounding areas, the document preview system identifies comments for the native document and determines the location to display the comment using native objects associated with the comment. When a new comment is received from a user for a preview of a native document, the document preview system determines native objects for the new comment that match a user's selection for placing the new comment. The new comment is inserted with the native objects in the native document.