We explore objects which are used to span knowledge boundaries (Carlile, ) in order to establish shared understanding in virtual innovation communities. In particular, the use of a mix of such boundary objects during collaboration on a virtual whiteboard is studied. Five collaborations with in total 31 participants are analyzed on the micro level of activities. We conceptualize collaboration activities according to Dennis et al. () as conveyance of information and convergence on meaning. Both, conveyance and convergence activities are necessary to establish shared understanding. Our results show why and how boundary objects are used specific to conveyance or convergence activities. We, thus, provide confirmative empirical evidence for the theoretical propositions of Dennis et al. () and extend current research on knowledge sharing in virtual innovation by showing how exactly boundary objects contribute. Practical implications include propositions for the design of collaboration platforms and innovation processes.