Scribd, a social publishing website, is being sued for copyright infringement for allowing the uploading of infringing works, and also for using the works themselves to filter for copyrighted work upon receipt of a takedown notice. While Scribd has a possible fair use defense, given the transformative function of the filtering use, Victoria Elman and Cindy Abramson argue that such filtration systems ought not to constitute infringement, as long as the sole purpose is to prevent infringement.