The United States v. Coolidge, et al was a Supreme Court case that dealt with the issue of whether or not certain lands in Maine were rightfully owned by the state or if they belonged to Massachusetts. The court found that although Massachusetts had originally granted these lands to settlers, it did not have any authority over them since Maine had become an independent state and therefore held title to all unappropriated land within its borders. Furthermore, the court ruled that even though some of these settlers may have been able to prove their ownership through deeds from Massachusetts prior to Maine's independence, those deeds would no longer be valid due to changes in jurisdiction and laws between states. As such, this ruling established precedent for how disputes over land titles should be handled when one state is ceded from another.

In the United States v. Coolidge, et al., Chief Justice John Marshall delivered a dissenting opinion in which he argued that Congress had no authority to pass laws concerning land titles and transfers within states. He reasoned that such matters were reserved for state legislatures under the Tenth Amendment of the Constitution, as they are not among those powers delegated to Congress by Article I, Section 8. Furthermore, Marshall asserted that if Congress was allowed to regulate these matters then it would be able to interfere with any other subject traditionally left up to individual states' discretion. As such, he concluded that this law was unconstitutional and should be struck down on grounds of federalism and separation of powers between different branches of government.