We report the results of the photometric and spectroscopic monitoring campaign of the transient SN 2007sv .
The observables are similar to those of type IIn supernovae , a well-known class of objects whose ejecta interact with pre-existing circum-stellar material .
The spectra show a blue continuum at early phases and prominent Balmer lines in emission , however , the absolute magnitude at the discovery of SN 2007sv ( M _ { R } = - 14.25 \pm 0.38 ) indicate it to be most likely a supernova impostor .
This classification is also supported by the lack of evidence in the spectra of very high velocity material as expected in supernova ejecta .
In addition we find no unequivocal evidence of broad lines of \alpha - and/or Fe-peak elements .
The comparison with the absolute light curves of other interacting objects ( including type IIn supernovae ) highlights the overall similarity with the prototypical impostor SN 1997bs .
This supports our claim that SN 2007sv was not a genuine supernova , and was instead a supernova impostor , most likely similar to the major eruption of a luminous blue variable .