In Wikipedia's earliest years, copyright tags were not used. Early editions of the "Contributors' rights and obligations" section of Wikipedia:Copyrights (example, from 2002) specified that all contributions to Wikipedia were licensed under the GFDL, and this wording remained in the 8 May 2006 version of the page; images were accepted as automatically GFDL unless there was a reason to suspect copyright infringement, similar to what we still do with textual contributions. From the project's earliest years, people uploaded images under various free licenses, and copyright tags were eventually created to identify the license(s) covering each image. However, because these tags were not required and because the submission of content caused an image to be GFDL-licensed, many images lacked them, causing confusion. Accordingly, the Wikipedia:Untagged images project was created in 2004 to tag non-problematic images that didn't yet have tags, and work continued into 2006. This project being basically complete, WP:CSD criterion I4 (now F4) was expanded on 11 May 2006 to permit the deletion of images with no copyright tags.

Since changes to policies generally grandfather pages that were created in compliance with existing policy, pre-May 2006 images should not be deleted merely because the uploader did not add a non-required copyright tag. Of course, such images must still be deleted if they can be shown to be copyvios, and they may still be deleted for reasons unrelated to copyright.