The presentation deals with the ductile damage and failure behavior of thin sheet metals under non-proportional loading. For this purpose, new biaxial geometries of flat specimens that allow a wide range of loading conditions are tested and corresponding numerical simulations revealing the stress state of the relevant parts are presented. Biaxial experiments with suitable specimens can be used to generate wide variety of stress states in a targeted manner and consequently the investigation of different non-proportional loading paths is enabled. In this context, experiments with thin sheet metals (thickness 1 mm and below) are very difficult to realize because notches cannot be introduced in the thickness direction and stability problems can occur very quickly. Furthermore, for this class of materials plastic anisotropic behavior can not be neglected and has to be reflected in the material modeling as well as in the design of the biaxial test series. New, specially developed specimens for thin sheets are presented and investigated experimentally as well as numerically. Here, non-proportional load paths are considered in two different ways: on the one hand, specimens are fabricated from preformed sheets and then loaded to failure on different proportional load paths, and on the other hand, specimens are fabricated from as-supplied material and subjected to non-proportional loads to failure. The strain fields at the specimen surface are evaluated by digital image correlation at significant points of the loading history. Corresponding numerical simulations considering plastic anisotropic behavior reveal the present stress states and facilitate the analysis of the stress-state-dependent damage and failure behavior.