What does it mean to call something ‘knowledge’ today? What does this recognition or translation require? And what does it entrain? This introduction makes a novel synthesis of contributions to the Special Issue and advances original observations regarding the ‘mythic’ qualities of Intellectual Property Law, the precipitation of ‘nature’, and the importance of attending to what is lost when things and practices are also ‘knowledge’. The papers cohere around a remarkable and timely set of observations and critiques: critiques of the way the knowledge economy makes demands and defines expectations about value; of how intellectual property law lies behind and shapes exclusions, inclusions and inequalities; of the ‘mythic’ status of assumptions informing laws about ownership; and the implicit hierarchy contained within types of knowledge as understood through the categories of western science. By taking up effect rather than veracity and certainty, the contributors are drawn into the very contestations that surround ‘knowledge’ without removing the work of definition from those making claims or feeling the effects of something appearing as ‘knowledge’. A common observation is to notice how equivalences across practices, made for the purpose of creating the possibility of exchange value (and thus of encouraging circulation) does its work at the expense of multiple aspects, values, and relations that are also discernable in social processes that produce ‘knowledge’. Contributors leave the definition of knowledge to ethnographic subjects. That is, they attend to where and how things come to be called knowledge, and for what reasons.