It seems like I didn't make myself clear. I know how to do that, just that the level of security is not good enough for me. If I don't give user1 any permission on space_B of user2, the document cannot be moved in space_B of user2 as desired. It's an error "Failed to approve the document due to system error: 04175066 Access Denied. You do not have the appropriate permissions to perform this operation." As far as I have seen until now the only way to solve this is to give user1 at least collaborator permission on space_B of user2, which is not the security that I need. I don't want user1 to have any permission on space_B of user2, that's the idea. I want to know what and where needs to modified (config files, java code) to avoid this error in order to fully secure my workflow. Thanks.