"it is worth now considering the (largely unrecognised) aspects of the group that we might consider to be disadvantaging and disempowering forms of teacher activity. In the first instance then, we need to acknowledge the embedding of the group within Facebook's business model of extracting surplus value from the unpaid labour of its users. As such, the creation of content on the group was generating data that was saleable to advertisers. As we saw, a group of 13,000 teachers is a profitable site through which to sell targeted advertisements for technology products or, indeed, for marketers to directly infiltrate. Any teacher, or indeed any user, using Facebook is inevitably working for Facebook as well as for themselves (Fuchs, 2014). Also problematic is Facebook's use of the group to generate surplus value from the objectification of knowledge derived from teachers’ professional experiences of working in Swedish public education (see Zukerfeld, 2017). That this knowledge is being used for profit by a US corporation lends weight to Srnicek's (2016) contention that platforms such as Facebook are parasitical to other value-producing industries."