Thanks for your photos Anne, yep it's the same bowl, but I have no marks on mine at all visible. I've been over its bottom feeling for anything that could conceivably be a mark as well and nothing at all. I suppose it could be from a mould that is so worn the lettering has faded to nothing?
Also I agree with the vase on 1st Glassman... I'd not noticed that before, but it looks like it's from the same design series. I wonder who made them and what else they did and in what other colours? So far we've seen our oval bowls, Pamela's footed bowl, and now Tony's vase - in blue, pink and amber.