Amazon has also engaged in activities where it censored customers' negative reviews. For example, in 2012, authors Joe Konrath and Steve Weddle reported that Amazon deleted their reviews in response to a wave of "sock puppet" controversies. In the scandal, many authors used anonymous accounts on Amazon to provide positive reviews for their own books and negative reviews for the competitors' work, on grounds not of quality but of who wrote the books. Amazon sought to rectify this problem by prohibiting authors from publishing reviews about other writers' works.