A judgment has no force outside the rendering state until it is domesticated.
Registration. Most states have adopted a uniform enforcement act permitting a judgment creditor to file an authenticated copy of the judgment with an affidavit, after which it is treated as a judgment of that state.
Notice. To the debtor at the address in the affidavit, with a period during which enforcement is stayed and during which the debtor may raise defences.
Defences available. Lack of personal or subject matter jurisdiction in the rendering court; lack of due process; fraud in procurement; and satisfaction. The merits may not be relitigated.
Alternative route. An action on the judgment, which is slower and is used where the registration procedure is unavailable or where the judgment is not final.
Limitation periods. The enforcing state’s period for enforcing a foreign judgment, and borrowing statutes, which can bar enforcement of an old judgment even where it remains enforceable at home. Renewing the judgment in the rendering state before it lapses is what preserves it.
Practical sequence. Locate assets first, domesticate in the states where they are, and pursue post-judgment discovery in the rendering state where the debtor is subject to its jurisdiction.