Sometimes I have projects that I rework from one version of visual studio to another. So I'll have two versions of visual studio open on the same computer at the same time. It seems like my Resharper 10 Ultimate doesn't allow for this scenario by disactivating one of the licenses. I'm hoping that as a single user license holder I can use the product on multiple versions of visual studio, even if they are opened simulatiously. It does make sense to me that if I'm on a single computer, and the only person logged in, that I should be allowed to bounce around from VS 2012 to VS 2015 without having my license deactivated.