final judgment rule
only a final judgment may be appealed
final judgment
one that ends the entire litigation on the merits and leaves nothing for the court to do but execute on the judgment
Rationale for final judgment rule
2. avoids delay
interlocutory appeal
an appeal that is taken before a final judgment has been entered
interlocutory order
an order that does not dispose of the entire action
collateral order doctrine
an exception to the finality principle that allows review of interlocutory orders that are separable from the merits of the case, final, urgent, and involve important but unsettled questions of law
An interlocutory order may be appealed as a collateral order if: