ATLAS is one of the major experiments at the Large Hadron Collider at CERN. Four Swedish universities participate in ATLAS operations and data analysis: KTH, LU, SU and UU. Data analysis and simulations involve very large amounts of data; some of this is stored permanently in Grid data centres, such as the Nordic Tier1, but some need to be kept temporarily. Typically initial derivations are done on the Grid, and final analysis is done close to the users, and require hundreds of Terabytes of local storage. At the moment 3 of the 4 Swedish ATLAS groups have local Grid-enabled storage, some of which is approaching end of life. With this proposal, we expect that a shared Swestore partition can be allocated instead, such that the groups can collaborate in a more coherent and scalable manner. The partition should be exposed to the Grid, and be able to receive data produced by Swedish ATLAS users worldwide. It should be also possible for the entire international ATLAS community to have read access to the data.