The Greenland Sovereignty Protection Act seeks to prevent the United States from acquiring Greenland or influencing its self-determination. This bill prohibits the use of federal funds for any activity that supports, directs, or facilitates the invasion, annexation, purchase, or other form of acquisition of Greenland by the U.S. government. It also bans federal funding for increasing the presence of U.S. Armed Forces or any financial investment in Greenland beyond pre-enactment levels, adjusted for inflation. Additionally, the Act prohibits funding for any public or private influence campaigns aimed at swaying the self-determination of the people of Greenland. A waiver for these prohibitions is only possible through a specific statutory authorization enacted after this Act, which must explicitly cite the waiver provision.