Are we sure of what way we are looking at this?
I have an older Riedel Cardonnay glass that has a mark that looks like "ac" if you look at it from the top, but "upside down"? If you look at it from the bottom, it looks like "gc", or a backwards "c" and a "b". I'm not evenb sure what MY glass is supposed to be saying!
The way I would "normally look at the rim, it looks like a backwards "c" and an "r"? Newer Riedels are different, I think, but I will have to look at a few...