Samuel Provost is an Associate Professor in Archeology and Art History of Late Antiquity at the University of Lorraine in Nancy, France. He has done exhaustive research on the dating of Gallé glassware based on the various signatures, as per the chart below. This research updates some of the assumptions from the previous work of others.
I have a matching set of 2 signed Galle lamps. They are a very unique design with a blue background and clusters of spotted rust colored flowers flowing down the shade and base. The base is also lighted and the very bottom part of the base is almost a tiger pattern. I would be happy to send a few pictures if you think it would be helpful in determining the authenticity/value of the items. Thank you – Jeff