Syntactically and morphophonologically full forms of the French disclaimer je sais pas ‘I don’t know’ in interaction tend to be deployed as epistemic disclaimers whereas lowered forms tend to be like discourse markers. The latter emerge in diverse sequential settings in mid-turn position, fulfilling interactional aims like hedging, floor-holding or indexing approximation. By contrast, in turn-initial and turn-final position, they mainly emerge in replies to questions, and are especially involved in the sequential organization of turns and actions.