The PINAS platform provides support to collaboratively and consistently produce shared documents in the Web environment. Such documents may include possible costly multimedia resources, whose management raises important issues due to the constraints imposed by Web technology. In this paper, we present a flexible service for distributing shared Web documents across authoring group sites. To carry out distribution, our approach takes into account the current organization of the involved sites, the access rights granted to the co-authors and the site storage capabilities. Scenarios are used to motivate the need for robust mechanisms for the management of shared Web documents and their resources, and to illustrate how our approach addresses these issues.