Flickr asks that users use filters to restrict viewership of content that's inappropriate for children. Tumblr is that rare commercial platform (owned by Yahoo) that doesn't censor its content very much. Posts are supposed to be labeled NSFW, so that those who would like to may block such content, and explicit videos are not supposed to be uploaded, but they may be embedded."We're not in the business of hosting adult-oriented videos (and it's fucking expensive)," the site's community guidelines state According to the study, very few people make porn for these sites: only about .1% of Tumblr users and .43% of Flickr users. What's interesting is when you look at how many people consume it: Porn consumers — defined as people who follow the porn producers and sometimes share or reblog their posts — account for 22.5% of Tumblr users. Because of those consumers' reblogs, another 28.5% of Tumblr users are unintentionally exposed to porn. So that adds up to more than half of Tumblr users making or watching porn on the site. Flickr doesn't really allow for sharing, so only 5% of users counted as consumers and 12% were unintentionally exposed.