Diversity Jurisdiction?

How long must a plaintiff be a resident of a new home in a new state before Diversity Jurisdiction no longer applies? Is 1 year enough and if so, would that be before or after they file taxes?
Thank You. ONE
For Federal Diversity jurisdiction to apply, diversity must exist at the time of filing. One case upheld diversity where the Plaintiff hade established his residency only three days before filing.
I think it would be immediate. It takes a while to establish residency for other purposes, but for purposes of jurisdiction all that would matter is your residency at the time of suit. Also, residency is not just where you live, it is a legal determination of where you intend to have your home. One year is enough and filing taxes would be pretty immaterial.


Answer:
Plaintiff's almost never have to overcome diversity. You can sue someone in any state that can legitimately hear the case. As a plaintiff this is generally not an issue. Defendants use it as a way to get out of a suit.

If as a plaintiff you are willing to avail yourself of the courts in a state you have overcome any issues you will have with diversity.

Generally the factors that go towards residency and domicile focus on your intent to stay in the state and not the length of time you are there but the rules for establishing it are usually found in the rules of civil procedure section of your state's codes.
If you are talking about federal diverstiy jurisidiction, then the diversity must exist at the time of filing. You cannot divest the court of diverstiy jurisdiction by subsequently defeating diversity after the case is filed - that would be unfair.

Determining diversity has to do with establishing domicile in a state. That is a question of intent.