This paper investigates a complex collaborative e-government initiative in Sweden using Boundary Object theory. 22 Swedish authorities have a joint mission to create a shared submission function to facilitate the communication and collaboration between numerous stakeholders such as forest owners, businesses and several other state-and local authorities. A case study approach is used where data is collected through in-depth interviews with different stakeholders, document studies and one focus group with project managers. Four boundary objects are identified: project, shared submission function, effects analysis and appropriation direction. By analyzing these four we describe how boundary objects are used to facilitate collaboration within an open government ecosystem.