After infiltrating the infamous Bonanno crime family, and to a lesser extent the Colombo family, between 1976 to 1981, he spent the years that followed testifying in several trials that led to more than 100 federal convictions.

This kind of proves my point on him testyfying about the mob. And the below says the 5:

This artist drawing shows undercover FBI agent Joseph Pistone, center, questioned by Assistant U.S. Attorney Barbara Jones at federal court in Manhattan, New York City on Tuesday, August 3, 1982, during the trial of five men accused of violating racketeering laws. At left is one of the defendants, Benjamin “Lefty” Ruggiero.