Wow.. if that really is his signature, then it is the best Sinatra signature I've ever seen. If you google his signature, it looks exactly like the font from his cover albums. Usually, his signature are scribbles and it changes overtime. The signature you have is very similar to his signatures during the 1950s. I would say your piece is authentic but note that it is too perfect of a signature.

Real? Found it in my Grandmother's closet. She owned EVERYTHING Sinatra, so I wouldn't be surprised if it was real. But, obviously, we're talking about Frank Sinatra. So.

What do you guys think? It's on the cover of "It Might As Well Be Swing".