In focus for this study are epistemic displays in peer talk, throughout collaborative writing events in the context of inquiry learning. Conversational data was obtained from small groups of primary school students (aged 8-12 years). By means of Conversation Analysis, we found that epistemic displays are produced as (i) accounts, (ii) responses to a request for information, (iii) other-corrections, and with reference to the propositional content of a previous epistemic display, as (iv) disagreements, and (v) expansions. The occurrence of epistemic displays is related to specific aspects of the writing activity, concerning contexts that require accounting or evoke expansions, and features of the participation framework. Our research contributes to the understanding of how collaborative writing activities establish contexts for sharing and discussing knowledge in peer talk, and are worth taking into account for educational professionals, when designing collaborative writing activities for that purpose.