We present results of a Bayesian analysis of radial velocity ( RV ) data for the star HIP 5158 , confirming the presence of two companions and also constraining their orbital parameters . Assuming Keplerian orbits , the two-companion model is found to be e ^ { 48 } times more probable than the one-planet model , although the orbital parameters of the second companion are only weakly constrained . The derived orbital periods are 345.6 \pm 2.0 d and 9017.8 \pm 3180.7 d respectively , and the corresponding eccentricities are 0.54 \pm 0.04 and 0.14 \pm 0.10 . The limits on planetary mass ( m \sin i ) and semimajor axis are ( 1.44 \pm 0.14 M _ { J } , 0.89 \pm 0.01 AU ) and ( 15.04 \pm 10.55 M _ { J } , 7.70 \pm 1.88 AU ) respectively . Owing to the large uncertainty on the mass of the second companion , we are unable to determine whether it is a planet or a brown dwarf . The remaining ‘ noise ’ ( stellar jitter ) unaccounted for by the model is 2.28 \pm 0.31 m/s . We also analysed a three-companion model , but found it to be e ^ { 8 } times less probable than the two-companion model .