Board Thread:Theories and Speculation/@comment-31477926-20170702121758/@comment-734582-20170817145111

321Z3R0 wrote: Besides, nothing is invincible. Context is important here. At the moment Zetsu proclaimed him invincible, many powerful people were dead and a new generation of powerful people had yet to take their place. Plus, i have serious doubts whether Zetsu would include Nagato or Obito in this comparison, since i don't see why they would.

Sure, people like Hashirama or Madara or Hagoromo could take Itachi, but they were dead. Others like an edo Raikage or an edo Mu may have been able to defeat him, but there was no indication of the Kabuto alliance at that moment and no reason to believe many powerful people would be summoned from the afterlife.

Similarly, future forms like Juubi Obito or Juubi Madara were so far out of the scope that comparisons to them would be useless.

So in short, yes, at that moment Itachi was probably invincible.