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Abstract The KATRIN experiment aims at measuring the electron neutrino mass with a sensitivity of 0.2 eV/c $$^2$$ 2 after 5 years of data taking. Recently a new upper limit for the neutrino mass of 0.8 eV/c $$^2$$ 2 (90% CL) was obtained. To reach the design sensitivity, a reduction of the background rate by one order of magnitude is required. The shifted analysing plane (SAP) configuration exploits a specific shaping of the electric and magnetic fields in the KATRIN main spectrometer to reduce the spectrometer background by a factor of two. We discuss the general idea of the SAP configuration and describe the main features of this novel measurement mode.