In this chapter, I have considered the question as to whether, and in which sense, collaboratively created scientific knowledge can be considered irreducibly collective. I have based my consideration upon the empirical insights into the two research groups I have studied. On the basis of these insights, I have argued that the joint commitment approach to collective knowledge does not apply well to collaboratively created scientific knowledge. Instead, I have suggested pursuing the epistemic dependence approach to collective scientific knowledge. I have argued that scientific knowledge is collective when mutual epistemic dependence prevents individual scientists from providing a scientific justification for the piece of knowledge in question. In formulating this notion of collective scientific knowledge, I have built upon the work of de Ridder (2014).
In contrast to de Ridder, however, I do not confine collective scientific knowledge to cases of mutual epistemic dependence that are opaque. As a consequence, the notion of collective scientific knowledge that I propose (ED**) is a rather broad notion, applicable to much of collaboratively created scientific knowledge—only such a notion, I believe, acknowledges the collective dimension of actual scientific practice.