He was the don of the Tattaglia family
Who says so..?
I found it on wikipedia and a few other godfather sites. One thing is for sure he was never a Corleone since joey zasa ghad control for at least a few years
What's the original source?
That Zasa had control doesn't mean that Altobello couldn't be a Corleone. If you paid much attention when you viewing Part III you would have noticed that Zasa was nothing more than a pawn used by Lucchesi and Altobello.