How many subspecies of tiger are presumed extinct?

Answer 1

It is generally considered that three subspecies, the Caspian Tiger, the Javan Tiger, and the Balinese Tiger, all became extinct in the past century. There are the odd sightings, and surveys for information related to those are conducted. But it is "generally" agreed on, through out the scientific community, that all three are extinct. It needs to be understood, that it is always difficult to prove a negative or in other words, that "something does not exist". As the Ivory-billed Woodpecker so wonderfully proved. For more information, please see sites listed.