For over a century American courts and text writers have referred to the administration of a decedent's estate as a proceeding in rem. Indeed, it has recently been asserted that a probate proceeding is "universally recognized as a proceeding in rem." But more cautious persons have been content to suggest that it is at least "quasi in rem," or have carefully skirted the fog which is wont to envelop this area of the law and given it silent treatment. Thus, the American Law Institute Restatement of the Law of Judgments ( which purports to include the law of probate decrees) gives examples of judgments in rem, and mentions in that connection judgments of a court of admiralty, judgments under land registration statutes and proceedings for forfeiture of things used in violation of law, but does not refer to probate decrees. At a later point, after positively asserting that an admiralty proceeding to enforce a maritime lien on a vessel, or a proceeding for a registration of title to land is in rem, it continues with this guarded observation: "So, also, probate courts, acting within their jurisdiction, can give judgments in rem, binding on all the world."
Lewis M. Simes,
THE ADMINISTRATION OF A DECEDENT'S ESTATE AS A PROCEEDING IN REM,
Mich. L. Rev.
Available at: https://repository.law.umich.edu/mlr/vol43/iss4/4