I don't know of enough places that use Nexus to say whether it is common practice or not, however we do not bundle jar files with sources at my place of employment where we do use Nexus. If we wanted to bundle sources into jar that would have to be done so explicitly, as it would require something like mavens source plugin. In fact in maven the standard seems to be to include sources in a separate jar, if one wants to publish the sources i.e. again requiring explicit choice and configuration.