Written interaction between pre-service teachers engaged in progressive inquiry using Knowledge Forum in two intense summer courses were analyzed to detect and rank those students in terms knowledge sharing, pressing on for further inquiry and the number of partners they communicated with. Social network analysis techniques were employed to cluster students in terms of their network centrality using a Freeman's betweenness value, where higher values indicated more communication flow occurred through that person. An aggregate score is calculated for each student and they were ranked into four levels of epistemic agency ranging from exceptional to low. Nearly half of the students in both courses ranked in the lowest level of epistemic agency interpreted as following mostly their own epistemic goals with minimal knowledge sharing with few partners and mediating little of knowledge sharing and collective inquiry. There were two to three students in each course with outstanding score in all of the five criteria and the others dispersed evenly from moderate to high. Both courses gave a low network centrality value indicating that the communication was not concentrated over a few individual but evenly scattered among the members. Epistemic agency is defined, and the analysis and rankings are elaborated with tables and charts. (Contains 5 tables.)