Hi and welcome!

Lamp shades can be notoriously difficult to identify. Even when they are by a well known maker, they tend to involve specific special production techniques that remove them from the general production line, and so do not often have distinguishing features of that production line.
Having said that, this shade does look rather special, I would hope somebody might be able to help you.
Your location on the planet might help us a little, although glass does travel all over the world, often the place the person who has the glass lives in, is a good place to start.