The bowl does say "Murano" on it, so my last comment about perhaps being from another place didn't make any sense. I have not seen any of the Ponti designs signed like this. Ponti's Murano glass tends to be colorful and complex, so I am not sure that the signature is not a forgery. The only Murano work that I know was designed by Ponti was Venini and had the Venini signatures. Perhaps he designed for some other companies that I don't know about? Without finding this specific design, it is difficult to say.
Anita