There are a couple of claims for these bowls: Salviati and Nicholas Lutz. I don't see Sowerby in this one, but I don't know a lot about them. It may be that both Salviati and Lutz did the same designs, so it isn't an either/or. Being a Murano person, I favor Salviati... but that doesn't mean that it isn't Lutz. I have been wrong more than I care to admit. :spls2: