Off-shore seismicity in Italy is, except for a few areas, located outside of the monitoring networks. This mislocation between networks and hypocentral locations causes a coupling in resolving the inverse problem of the earthquakes location with an enough quality. To reduce these bad effects, a further work it was necessary using more complex location techniques and appropriate tuning of the parameters of the location code. In this presentation we show the preliminary results of the draft catalogue containing earthquakes between 2005 and 2015.