The label used is quite old, before the time when glassmasters started to use their own label with name (from around 21 century).
Your label states Made in Italy, Murano. It is an authentic Murano Glass but it is quite difficult to guess the masterglass. Based on my knowledge it could be made by Oball furnace. Please have a look at this example Oball dolphin
. However, the dolphin sculpture was replicated by several other masterglasses...
Love Murano Glass
Always Italian Glass