[Under the "probate exception" to federal jurisdiction, federal courts sometimes decline to hear cases that are essentially disputes over property referenced in a will and controlled by a state probate court. In the excerpt quoted below, a court observed that due to the similarity between wills and will substitutes, the probate exception might apply even in the presence of a legal instrument that was not technically a will.]
"The plaintiffs argue that the probate exception is inapplicable here because this action relates to the execution of an inter vivos trust, not to a will. We reject such a per se rule. The inter vivos trust is clearly a will substitute. However, the fact that this case [involves] a will substitute does not automatically render the probate exception applicable."